Develop Reference

How to Figure out the MAX and MIN of Groups that have been Added together

How do would you get the MAX value of a column that has been grouped and add together by _id.
So something like this:
I then want to display the MAX value of the four groups, as well as the MIN value of the four groups.
Something like this Scratch High = 702 / Scratch Low = 325
Is this possible with the built in Math functions of SQLite or would I need to write specific code to accomplish this? The actual number of groups will be more than 4, it will depend on how often the bowler actually bowls a series.
I haven't written any code for this as of yet, I am attempting to figure out if this is even possible before attempting to do so. Any suggestions would be welcome.
My attempt to integrate into my Project:
DatabaseHelper.java
public static final String DERIVEDCOL_MAXSCORE = "max_score";
public static final String DERIVEDCOl_MINSCORE = "min_score";
public Cursor getMaxMinScoresAllAndroid() {
SQLiteDatabase db = this.getWritableDatabase();
String tmptbl = "summed_scores";
String tmptblcol = "sum_score";
String crttmptbl = "CREATE TEMP TABLE IF NOT EXISTS " + tmptbl + "(" +
tmptblcol + " INTEGER" +
")";
String empttmptbl = "DELETE FROM " + tmptbl;
db.execSQL(crttmptbl);
db.execSQL(empttmptbl);
String[] columns = new String[]{"sum(score) AS " + tmptblcol};
Cursor csr = db.query(Game.TABLE_NAME,columns,null,null,Game.COLUMN_BOWLER_ID,null,null);
DatabaseUtils.dumpCursor(csr);
while (csr.moveToNext()) {
ContentValues cv = new ContentValues();
cv.put(tmptblcol,csr.getInt(csr.getColumnIndex(tmptblcol)));
db.insert(tmptbl,null,cv);
}
csr.close();
columns = new String[]{"max(" +
tmptblcol +
") AS " + DERIVEDCOL_MAXSCORE,
"min(" +
tmptblcol +
") AS " + DERIVEDCOl_MINSCORE};
return csr = db.query(tmptbl,columns,null,null,null,null,null);
}
public MaxMin getMaxAndminScoresAll() {
MaxMin rv = new MaxMin(0,0);
Cursor csr = getMaxMinScoresAllAndroid();
if (csr.moveToFirst()) {
rv.setMin(csr.getInt(csr.getColumnIndex(DERIVEDCOl_MINSCORE)));
rv.setMax(csr.getInt(csr.getColumnIndex(DERIVEDCOL_MAXSCORE)));
}
csr.close();
return rv;
}
BowlerProfileViewActivity.java
public class BowlerProfileViewActivity extends AppCompatActivity {
Bowler bowler;
private DatabaseHelper db;
private static final String PREFS_NAME = "prefs";
private static final String PREF_BLUE_THEME = "blue_theme";
private static final String PREF_GREEN_THEME = "green_theme";
private static final String PREF_ORANGE_THEME = "purple_theme";
private static final String PREF_RED_THEME = "red_theme";
private static final String PREF_YELLOW_THEME = "yellow_theme";
#Override
protected void onResume() {
super.onResume();
db = new DatabaseHelper(this);
//mAdapter.notifyDatasetChanged(db.getAllLeagues());
}
#Override
protected void onCreate(Bundle savedInstanceState) {
//Use Chosen Theme
SharedPreferences preferences = getSharedPreferences(PREFS_NAME, MODE_PRIVATE);
boolean useBlueTheme = preferences.getBoolean(PREF_BLUE_THEME, false);
if (useBlueTheme) {
setTheme(R.style.AppTheme_Blue_NoActionBar);
}
boolean useGreenTheme = preferences.getBoolean(PREF_GREEN_THEME, false);
if (useGreenTheme) {
setTheme(R.style.AppTheme_Green_NoActionBar);
}
boolean useOrangeTheme = preferences.getBoolean(PREF_ORANGE_THEME, false);
if (useOrangeTheme) {
setTheme(R.style.AppTheme_Orange_NoActionBar);
}
boolean useRedTheme = preferences.getBoolean(PREF_RED_THEME, false);
if (useRedTheme) {
setTheme(R.style.AppTheme_Red_NoActionBar);
}
boolean useYellowTheme = preferences.getBoolean(PREF_YELLOW_THEME, false);
if (useYellowTheme) {
setTheme(R.style.AppTheme_Yellow_NoActionBar);
}
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_bowler_profile_view);
Intent intent = getIntent();
Boolean shouldUpdate = getIntent().getExtras().getBoolean("shouldUpdate");
String savedLeagueId = intent.getStringExtra("leagueId");
String savedBowlerId = String.valueOf(getIntent().getIntExtra("bowlerId",2));
int bowlerId = Integer.valueOf(savedBowlerId);
getBowlerProfile(savedLeagueId, bowlerId);
// Get The min and max score
MaxMin bowlerMaxMin = db.getMaxAndminScoresAll();
Log.d("SCORES",
"\n\tMaximum Score is " + String.valueOf(bowlerMaxMin.getMax()) +
"\n\tMinimum Score is " + String.valueOf(bowlerMaxMin.getMin()));
}
public void getBowlerProfile(String savedLeagueId, int savedBowlerId) {
String bn, ba, bh;
SQLiteOpenHelper database = new DatabaseHelper(this);
SQLiteDatabase db = database.getReadableDatabase();
Cursor viewBowlerProfile = db.query( Bowler.TABLE_NAME,
new String[]{Bowler.COLUMN_ID, Bowler.COLUMN_LEAGUE_ID, Bowler.COLUMN_NAME, Bowler.COLUMN_BOWLER_AVERAGE, Bowler.COLUMN_BOWLER_HANDICAP, Bowler.COLUMN_TIMESTAMP},
Bowler.COLUMN_ID + "=?",
new String[]{String.valueOf(savedBowlerId)}, null, null, null, null);
if (viewBowlerProfile.moveToFirst()) {
//Prepare League Object
bowler = new Bowler(
viewBowlerProfile.getInt(viewBowlerProfile.getColumnIndex(Bowler.COLUMN_ID)),
viewBowlerProfile.getString(viewBowlerProfile.getColumnIndex(Bowler.COLUMN_LEAGUE_ID)),
bn = viewBowlerProfile.getString(viewBowlerProfile.getColumnIndex(Bowler.COLUMN_NAME)),
ba = viewBowlerProfile.getString(viewBowlerProfile.getColumnIndex(Bowler.COLUMN_BOWLER_AVERAGE)),
bh = viewBowlerProfile.getString(viewBowlerProfile.getColumnIndex(Bowler.COLUMN_BOWLER_HANDICAP)),
viewBowlerProfile.getString(viewBowlerProfile.getColumnIndex(Bowler.COLUMN_TIMESTAMP)));
final TextView bowlerName = (TextView) findViewById(R.id.tvBowlerName);
final TextView bowlerAverage = (TextView) findViewById(R.id.tvBowlerAverageValue);
final TextView bowlerHandicap = (TextView) findViewById(R.id.tvBowlerHandicapValue);
bowlerName.setText(String.valueOf(bn));
bowlerAverage.setText(String.valueOf(ba));
bowlerHandicap.setText(String.valueOf(bh));
//Close Database Connection
viewBowlerProfile.close();
}
//View League Profile Cancel Button
final Button cancel_button = (Button) findViewById(R.id.bCancel);
cancel_button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Log.d("SAVEDLEAGUEID_VAL", ">>" + String.valueOf(savedLeagueId) + "<<");
Intent intent = new Intent(getApplicationContext(), BowlerActivity.class);
intent.putExtra("leagueId", savedLeagueId);
startActivity(intent);
finish();
overridePendingTransition(0, 0);
/*Intent intent = new Intent(getApplicationContext(), BowlerActivity.class);
intent.putExtra("leagueId", savedLeagueId);
Log.d("LEAGUEID VALUE","value of leagueId = " + String.valueOf(savedLeagueId));
startActivity(intent);
finish();
overridePendingTransition(0, 0);*/
}
});
//Edit League Profile Cancel Button
final Button edit_button = (Button) findViewById(R.id.bEdit);
edit_button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
int bowlerId = bowler.getId();
Intent intent = new Intent(getApplicationContext(), BowlerProfileEditActivity.class);
intent.putExtra("bowlerId", bowlerId);
intent.putExtra("leagueId", savedLeagueId);
startActivity(intent);
finish();
overridePendingTransition(0, 0);
}
});
}
}
Logcat
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'ca.rvogl.tpbcui.utils.MaxMin ca.rvogl.tpbcui.database.DatabaseHelper.getMaxAndminScoresAll()' on a null object reference
at ca.rvogl.tpbcui.views.BowlerProfileViewActivity.onCreate(BowlerProfileViewActivity.java:79)
at android.app.Activity.performCreate(Activity.java:6679)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
Attempting to group by bowlerId and seriesId
public Cursor getMaxMinScoresAllAndroid(String bowlerId) {
SQLiteDatabase db = this.getWritableDatabase();
String tmptbl = "summed_scores";
String tmptblcol = "sum_score";
String tmpBowlerIdCol = "bowler_id";
String tmpSeriesIdCol = "series_id";
String crttmptbl = "CREATE TEMP TABLE IF NOT EXISTS " + tmptbl + "(" +
tmptblcol + " INTEGER," +
tmpBowlerIdCol + " TEXT," +
tmpSeriesIdCol + " TEXT)";
String empttmptbl = "DELETE FROM " + tmptbl;
db.execSQL(crttmptbl);
db.execSQL(empttmptbl);
String[] columns = new String[]{"sum(score) AS "};
Cursor csr = db.query(Game.TABLE_NAME,columns,null,null,Game.COLUMN_BOWLER_ID + " = '" + bowlerId + "'", Game.COLUMN_SERIES_ID,null,null);
DatabaseUtils.dumpCursor(csr);
while (csr.moveToNext()) {
ContentValues cv = new ContentValues();
cv.put(tmptblcol,csr.getInt(csr.getColumnIndex(tmptblcol)));
cv.put(tmpBowlerIdCol,csr.getInt(csr.getColumnIndex(tmpBowlerIdCol)));
cv.put(tmpSeriesIdCol,csr.getInt(csr.getColumnIndex(tmpSeriesIdCol)));
db.insert(tmptbl,null,cv);
}
csr.close();
columns = new String[]{"max(" +
tmptblcol +
") AS " + DERIVEDCOL_MAXSCORE,
"min(" +
tmptblcol +
") AS " + DERIVEDCOl_MINSCORE};
return csr = db.query(tmptbl,columns,null,null,null,null,null);
}
public MaxMin getMaxAndminScoresAll(String bowlerId) {
MaxMin rv = new MaxMin(0,0);
Cursor csr = getMaxMinScoresAllAndroid(bowlerId);
if (csr.moveToFirst()) {
rv.setMin(csr.getInt(csr.getColumnIndex(DERIVEDCOl_MINSCORE)));
rv.setMax(csr.getInt(csr.getColumnIndex(DERIVEDCOL_MAXSCORE)));
}
csr.close();
return rv;
}

You could do this (assuming the table is named myscores and the columns are _id and score) using :-
WITH cte1 AS
(
sum(score) AS sum_score
FROM myscores
GROUP BY _id
)
SELECT max(sum_score) AS min_score, min(sum_score) FROM cte1;
Using this would result in the following :-
Notes
AS is used to rename the output columns
without renaming the columns they would be named max(sum_score) and min(sum_score) respectively.
SQL As Understood By SQLite - Aggregate Functions
This utilises the SQLite aggregate functions max and min and the GROUP BY clause to aggregate the columns according to the _id column.
This also utilises a Common Table Expression (an intermediate/temporary table).
SQL As Understood By SQLite - WITH clause
Incorporating into an Android App (see note at end)
The following is an example App demonstrates how this can be incorporated fro Android :-
First a simple class for the Minimum and maximum vales (as used in the alternative getMaxAndMinScores method)
MaxMin.java (optional)
public class MaxMin {
private int min;
private int max;
public MaxMin(int min, int max) {
this.min = min;
this.max = max;
}
public int getMin() {
return min;
}
public void setMin(int min) {
this.min = min;
}
public int getMax() {
return max;
}
public void setMax(int max) {
this.max = max;
}
}
DBHelper.java
The subclass of SQLiteOpenHelper (just the one table name myscores)
public class DBHelper extends SQLiteOpenHelper {
public static final String DBNAME = "mydb";
public static final int DBVERSION = 1;
public static final String TB_SCORE = "myscores";
public static final String COL_SCORE = "score";
public static final String COL_ID = BaseColumns._ID;
public static final String DERIVEDCOL_MAXSCORE = "max_score";
public static final String DERIVEDCOl_MINSCORE = "min_score";
private static final String crt_myscores_sql = "CREATE TABLE IF NOT EXISTS " + TB_SCORE + "(" +
COL_ID + " INTEGER," +
COL_SCORE + " INTEGER" +
")";
public DBHelper(Context context) {
super(context, DBNAME, null, DBVERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(crt_myscores_sql);
}
#Override
public void onUpgrade(SQLiteDatabase db, int i, int i1) {
}
public long addScore(long id, int score) {
ContentValues cv = new ContentValues();
cv.put(COL_ID,id);
cv.put(COL_SCORE,score);
return this.getWritableDatabase().insert(TB_SCORE,null,cv);
}
public Cursor getMaxMinScores() {
String sum_score = "sum_score";
String cte1 = "cte1";
String rawqry = " WITH " + cte1 +
" AS " +
"(" +
"SELECT sum(" +
COL_SCORE +
") AS " + sum_score +
" FROM " + TB_SCORE + " GROUP BY " + COL_ID +
") " +
"SELECT " +
" max(" +
sum_score +
") AS " + DERIVEDCOL_MAXSCORE +
"," +
" min(" +
sum_score +
") AS " + DERIVEDCOl_MINSCORE +
" FROM " + cte1 + ";";
return this.getWritableDatabase().rawQuery(rawqry,null);
}
public MaxMin getMaxAndMinScores() {
MaxMin rv = new MaxMin(0,0);
Cursor csr = getMaxMinScores();
if (csr.moveToFirst()) {
rv.setMin(csr.getInt(csr.getColumnIndex(DERIVEDCOl_MINSCORE)));
rv.setMax(csr.getInt(csr.getColumnIndex(DERIVEDCOL_MAXSCORE)));
}
csr.close();
return rv;
}
}
MainActivity.java
The activity that a) adds some rows and then b) gets the maximum and minimum scores (twice using alternative methods) :-
public class MainActivity extends AppCompatActivity {
DBHelper mDBHlpr;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mDBHlpr = new DBHelper(this);
// Add Some scores
mDBHlpr.addScore(1,112);
mDBHlpr.addScore(1,123);
mDBHlpr.addScore(1,144);
mDBHlpr.addScore(2,212);
mDBHlpr.addScore(2,190);
mDBHlpr.addScore(2,300);
mDBHlpr.addScore(3,234);
mDBHlpr.addScore(3,134);
mDBHlpr.addScore(3,122);
mDBHlpr.addScore(4,100);
mDBHlpr.addScore(4,111);
mDBHlpr.addScore(4,114);
// Get The min and max scores example 1
Cursor csr = mDBHlpr.getMaxMinScores();
if (csr.moveToFirst()) {
int max_score = csr.getInt(csr.getColumnIndex(DBHelper.DERIVEDCOL_MAXSCORE));
int min_score = csr.getInt(csr.getColumnIndex(DBHelper.DERIVEDCOl_MINSCORE));
Log.d("SCORES",
"\n\tMaximum Score is " + String.valueOf(max_score) +
"\n\tMinimum Score is " + String.valueOf(min_score)
);
}
//Alternative utilising the MaxMin object
MaxMin mymaxmin = mDBHlpr.getMaxAndMinScores();
Log.d("SCORES",
"\n\tMaximum Score is " + String.valueOf(mymaxmin.getMax()) +
"\n\tMinimum Score is " + String.valueOf(mymaxmin.getMin())
);
}
}
IMPORTANT
The WITH clause was introduced in SQL 3.8.3, some older versions of Android (below lollipop (but can be device independent)) will not
support the WITH clause.
The following methods, as equivalents of getMaxMinScores and getMaxAndMinScores could be used for any Android version :-
public Cursor getMaxMinScoresAllAndroid() {
SQLiteDatabase db = this.getWritableDatabase();
String tmptbl = "summed_scores";
String tmptblcol = "sum_score";
String crttmptbl = "CREATE TEMP TABLE IF NOT EXISTS " + tmptbl + "(" +
tmptblcol + " INTEGER" +
")";
String empttmptbl = "DELETE FROM " + tmptbl;
db.execSQL(crttmptbl);
db.execSQL(empttmptbl);
String[] columns = new String[]{"sum(score) AS " + tmptblcol};
Cursor csr = db.query(TB_SCORE,columns,null,null,COL_ID,null,null);
DatabaseUtils.dumpCursor(csr);
while (csr.moveToNext()) {
ContentValues cv = new ContentValues();
cv.put(tmptblcol,csr.getInt(csr.getColumnIndex(tmptblcol)));
db.insert(tmptbl,null,cv);
}
csr.close();
columns = new String[]{"max(" +
tmptblcol +
") AS " + DERIVEDCOL_MAXSCORE,
"min(" +
tmptblcol +
") AS " + DERIVEDCOl_MINSCORE};
return csr = db.query(tmptbl,columns,null,null,null,null,null);
}
public MaxMin getMaxAndminScoresAllAndroid() {
MaxMin rv = new MaxMin(0,0);
Cursor csr = getMaxMinScoresAllAndroid();
if (csr.moveToFirst()) {
rv.setMin(csr.getInt(csr.getColumnIndex(DERIVEDCOl_MINSCORE)));
rv.setMax(csr.getInt(csr.getColumnIndex(DERIVEDCOL_MAXSCORE)));
}
csr.close();
return rv;
}
These utilise an intermediate temporary table so bypass the restriction of using WITH

Updating Database in Android

I am updating a record in Sqlite database through the function given below.Their is only 1 Table and a number of columns.Initially i am updating 3 columns. Problem i am facing :
1) The Problem is that in Logcat initial data is shown but updated data is not showing. Also Logcat not showing any error.
2) When i am displaying in Toast only last value which i added in database statically is showing. Initial two are not present in Toast.
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class ContractSqlite extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "thorcontract_Db";
// TABLE NAME
private static final String TABLE_NAME = "contract";
// COLUMN
private static final String PRIMARY_COLUMN = "heading";
private static final String CONTRACT_TITLES_TITLE = "cnttitle";
private static final String CONTRACT_TITLES_SUBTITLE = "cntSUBTITLE";
private static final String CONTRACT_TITLES_BIDID = "cntbidid";
private static final String LOADSUMMARY_HEADER = "lsheader";
private static final String LOADSUMMARY_FOOTER = "lsfooter";
private static final String SECTION1_TITLE = "s1title";
private static final String SECTION1_BODY = "s1body";
private static final String SECTION2_TITLE = "s2title";
private static final String SECTION2_BODY = "s2body";
private static final String SECTION3_TITLE = "s3title";
private static final String SECTION3_BODY = "s3body";
private static final String SECTION4_TITLE = "s4title";
private static final String SECTION4_BODY = "s4body";
private static final String SECTION5_TITLE = "s5title";
private static final String SECTION5_BODY = "s5body";
private static final String SECTION6_TITLE = "s6title";
private static final String SECTION6_BODY = "s6body";
private static final String SECTION7_TITLE = "s7title";
private static final String SECTION7_BODY = "s7body";
private static final String SECTION8_TITLE = "s8title";
private static final String SECTION8_BODY = "s8body";
private static final String SECTION9_TITLE = "s9title";
private static final String SECTION9_BODY = "s9body";
private String title = null, subtitle = null, bidid = null;
public ContractSqlite(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
}
#Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
String CREATE_CONTRACT_TABLE = " CREATE TABLE " + TABLE_NAME + "("
+ PRIMARY_COLUMN + " INTEGER PRIMARY KEY,"
+ CONTRACT_TITLES_TITLE + " TEXT ," + CONTRACT_TITLES_SUBTITLE
+ " TEXT ," + CONTRACT_TITLES_BIDID + " TEXT,"
+ LOADSUMMARY_HEADER + " TEXT," + LOADSUMMARY_FOOTER + " TEXT,"
+ SECTION1_TITLE + " TEXT," + SECTION1_BODY + " TEXT,"
+ SECTION2_TITLE + " TEXT," + SECTION2_BODY + " TEXT,"
+ SECTION3_TITLE + " TEXT," + SECTION3_BODY + " TEXT,"
+ SECTION4_TITLE + " TEXT," + SECTION4_BODY + " TEXT,"
+ SECTION5_TITLE + " TEXT," + SECTION5_BODY + " TEXT,"
+ SECTION6_TITLE + " TEXT," + SECTION6_BODY + " TEXT,"
+ SECTION7_TITLE + " TEXT," + SECTION7_BODY + " TEXT,"
+ SECTION8_TITLE + " TEXT," + SECTION8_BODY + " TEXT,"
+ SECTION9_TITLE + " TEXT," + SECTION9_BODY + " TEXT" + ")";
db.execSQL(CREATE_CONTRACT_TABLE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("DROP TABLE" + TABLE_NAME);
onCreate(db);
}
public void addRecord(String title, String subtitle, String bidid) {
SQLiteDatabase db = this.getWritableDatabase();
// String title1 = title;
// String subtitle1 = subtitle;
// String bidid1 = bidid;
ContentValues values = new ContentValues();
try {
values.put(CONTRACT_TITLES_TITLE, title);
values.put(CONTRACT_TITLES_SUBTITLE, subtitle);
values.put(CONTRACT_TITLES_BIDID, bidid);
db.insert(TABLE_NAME, null, values);
Log.i("Initial Data", " " + title + " " + subtitle + " " + bidid);
db.close();
} catch (Exception e) {
db.close();
}
}
public String[] getrecord() {
String selectQuery = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
if (cursor != null && cursor.moveToFirst()) {
title = cursor.getString(cursor
.getColumnIndex(CONTRACT_TITLES_TITLE));
subtitle = cursor.getString(cursor
.getColumnIndex(CONTRACT_TITLES_SUBTITLE));
bidid = cursor.getString(cursor
.getColumnIndex(CONTRACT_TITLES_BIDID));
// Dumps "Title: Test Title Content: Test Content"
Log.i("CONTRACTTITLES", "Title: " + title + " Content: " + subtitle);
cursor.close();
}
return new String[] { title, subtitle, bidid };
}
public int update(String title, String subtitle, String id) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(CONTRACT_TITLES_TITLE, title);
values.put(CONTRACT_TITLES_SUBTITLE, subtitle);
values.put(CONTRACT_TITLES_SUBTITLE, id);
return db.update(TABLE_NAME, values, PRIMARY_COLUMN + " =?",
new String[] { String.valueOf(1) });
}
}
Method Calling From Main Activity.
csq is database class object
for adding a record
csq.addRecord("abc", "xyz", "1234");
for updating
csq.update(cnttitle_str, cntsubtitle_str, cntbid_str);
for getting a record
String[] str = csq.getrecord();
Toast.makeText(getActivity(),
" " + str[0] + " " + str[1] + "" + str[2], Toast.LENGTH_LONG).show();

Updated data is not showing because you don't have a Log line there (if I understand you correctly).
You only get one line because you need to iterate through the Cursor and return a list or some such.

this sulotion is :
if you want to see all record , do this in your Database class :
public void showAllDBcells() {
String selectQuery = "SELECT * FROM " + TABLE_DB;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
if (cursor.moveToFirst()) {
do {
Log.d("your tag",cursor.getString(0));
Log.d("your tag",cursor.getString(1));
Log.d("your tag",cursor.getString(2));
// and for another data , just extends code for 3 4 5 ... columns
} while (cursor.moveToNext());
}
//
cursor.close();
db.close();
}
you can call method in your activity , and see your stored data from Database in Logcat .

Java Android SQLite duplicated values

I want to know how to check for duplicated fields in my database by updating it.
If the day and hour are the same in another row it must give an error.
DBHelper:
package me.wouter.schoolwork;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class Schedule {
public static final String KEY_ROWID = "_id"; //Row Id
public static final String KEY_HOUR = "schedule_hour";
public static final String KEY_DAY = "schedule_day";
public static final String KEY_LOCATION = "schedule_location";
public static final String KEY_SUBJECT = "schedule_subject";
public static final String KEY_START = "schedule_start";
public static final String KEY_END = "schedule_end";
private static final String DATABASE_NAME = "PlanYourDay";
private static final String DATABASE_TABLE = "schedule";
private static final int DATABASE_VERSION = 1;
private dBHelper classHelper;
private final Context classContext;
private SQLiteDatabase classDatabase;
public Cursor c;
private static class dBHelper extends SQLiteOpenHelper {
public dBHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" +
KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_HOUR + " TEXT NOT NULL, " +
KEY_DAY + " TEXT NOT NULL, " +
KEY_LOCATION + " TEXT NOT NULL, " +
KEY_SUBJECT + " TEXT NOT NULL, " +
KEY_START + " TEXT NOT NULL, " +
KEY_END + " TEXT NOT NULL);"
);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(db);
}
}
public Schedule(Context c){
classContext = c;
}
public Schedule open() throws SQLException{
classHelper = new dBHelper(classContext);
classDatabase = classHelper.getWritableDatabase();
return this;
}
public Schedule close(){
classHelper.close();
return this;
}
public long createEntry(String subject, String day, String hour,
String location, String start, String end) {
ContentValues cv = new ContentValues();
cv.put(KEY_SUBJECT, subject);
cv.put(KEY_DAY, day);
cv.put(KEY_HOUR, hour);
cv.put(KEY_LOCATION, location);
cv.put(KEY_START, start);
cv.put(KEY_END, end);
return classDatabase.insert(DATABASE_TABLE, null, cv);
}
public String getData() {
String[] columns = new String[]{KEY_ROWID, KEY_SUBJECT, KEY_HOUR, KEY_DAY, KEY_LOCATION, KEY_START, KEY_END};
c = classDatabase.query(DATABASE_TABLE, columns, null, null, null, null, null);
String result = "";
int iRow = c.getColumnIndex(KEY_ROWID);
final int iSubject = c.getColumnIndex(KEY_SUBJECT);
int iHour = c.getColumnIndex(KEY_HOUR);
int iDay = c.getColumnIndex(KEY_DAY);
int iLocation = c.getColumnIndex(KEY_LOCATION);
int iStart = c.getColumnIndex(KEY_START);
int iEnd = c.getColumnIndex(KEY_END);
for(c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
result = result + c.getString(iRow) + " " + c.getString(iSubject) + " " + c.getString(iHour) + " "
+ c.getString(iDay) + " " + c.getString(iLocation) + " " + c.getString(iStart) + " "
+ c.getString(iEnd) + "\n";
}
return result;
}
}
DB Inserter:
package me.wouter.schoolwork;
import android.app.Activity;
import android.app.Dialog;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class ScheduleTest extends Activity implements OnClickListener {
// object variables
Button bLoadSql, bSaveSql;
TextView viewSubject, viewDay, viewHour, viewLocation, viewStart, viewEnd;
EditText editSubject, editDay, editHour, editLocation, editStart, editEnd;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.sql);
allTheVariables();
bLoadSql.setOnClickListener(this);
bSaveSql.setOnClickListener(this);
}
private void allTheVariables() {
// defines variables in xml file
// buttons
bLoadSql = (Button) findViewById(R.id.bLoadSql);
bSaveSql = (Button) findViewById(R.id.bSaveSql);
// textviews
viewSubject = (TextView) findViewById(R.id.viewSubject);
viewDay = (TextView) findViewById(R.id.viewDay);
viewHour = (TextView) findViewById(R.id.viewHour);
viewLocation = (TextView) findViewById(R.id.viewLocation);
viewStart = (TextView) findViewById(R.id.viewStart);
viewEnd = (TextView) findViewById(R.id.viewEnd);
// edittext
editSubject = (EditText) findViewById(R.id.editSubject);
editDay = (EditText) findViewById(R.id.editDay);
editHour = (EditText) findViewById(R.id.editHour);
editLocation = (EditText) findViewById(R.id.editLocation);
editStart = (EditText) findViewById(R.id.editStart);
editEnd = (EditText) findViewById(R.id.editEnd);
}
#Override
public void onClick(View arg0) {
switch (arg0.getId()) {
case R.id.bLoadSql:
Intent i = new Intent("me.wouter.schoolwork.SCHEDULEVIEW");
startActivity(i);
break;
case R.id.bSaveSql:
boolean didItWork = true;
try{
String subject = editSubject.getText().toString();
String day = editDay.getText().toString();
String hour = editHour.getText().toString();
String location = editLocation.getText().toString();
String start = editStart.getText().toString();
String end = editEnd.getText().toString();
Schedule entry = new Schedule(this);
entry.open();
entry.createEntry(subject, day, hour, location, start, end);
entry.close();
}catch (Exception e){
didItWork = false;
String error = e.toString();
Dialog d = new Dialog(this);
d.setTitle("Failed");
TextView tv = new TextView(this);
tv.setText(error);
d.setContentView(tv);
d.show();
}finally{
if(didItWork){
Dialog d = new Dialog(this);
d.setTitle("Inserted");
TextView tv = new TextView(this);
tv.setText("Succes");
d.setContentView(tv);
d.show();
}
}
break;
}
}
}
And Viewer/Loader:
package me.wouter.schoolwork;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class ScheduleView extends Activity {
TextView subject;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.sqlview);
subject = (TextView) findViewById(R.id.subject);
Schedule info = new Schedule(this);
info.open();
String data = info.getData();
subject.setText(data);
info.close();
}
}
Thanks in advance!

It seems to me that what you need is a multi-column uniqueness constraint on your DB schema, with a suitable conflict clause:
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" +
KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_HOUR + " TEXT NOT NULL, " +
KEY_DAY + " TEXT NOT NULL, " +
KEY_LOCATION + " TEXT NOT NULL, " +
KEY_SUBJECT + " TEXT NOT NULL, " +
KEY_START + " TEXT NOT NULL, " +
KEY_END + " TEXT NOT NULL, " +
"UNIQUE (" + KEY_DAY + ", " + KEY_HOUR + ") ON CONFLICT ROLLBACK);"
);
This will generate a constraint violation error if the day/hour combination is not unique, without you having to write an explicit check.

Displaying data as listview And Getting an error NullPointerException

My problem is that I don't know how exactly I can display data from the database.
Here is my DatabaseHelper activity ( I've cut not needed code ), which open/close database and create tables.
final static String PN_TABLE = "Tablica_Poniedzialek";
static final String PN_KEY_ID = "_id";
final static String PN_KEY_TYPE_OF_SESSION ="type_of_session";
final static String PN_KEY_START_TIME ="start_time";
final static String PN_KEY_END_TIME ="end_time";
final static String PN_KEY_NAME ="name";
final static String PN_KEY_ROOM ="room";
Creating and adding data to the database works fine. The problem is that I don't know how exactly I should display data inserted into the database. I've tried using Cursors and List Adapter, but it seems that I've messed up something since application is forced to close every time I am launching it in an Emulator.
This is my activity which is responsible for getting data from Database and then displaying it. I have no clue how actually I can display data as a list view. I am not sure which method would be better, the one which creates list ( I believe that it does ) or one that simply fetch data from database. But, let's say that the first one is correct, then the question is how can I actually display all the data ?
package com.projekt;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.app.ListActivity;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
public class PoniedzialekActivity extends ListActivity implements OnClickListener{
private Button butPnAdd;
private DatabaseHelper dbhelper;
private SQLiteDatabase db;
Cursor cursor;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_poniedzialek);
butPnAdd = (Button) findViewById(R.id.butPnAdd);
butPnAdd.setOnClickListener(this);
List<Poniedzialek> lista_poniedzialek = getAllPnSession();
this.setListAdapter(new ArrayAdapter(this, android.R.layout.simple_list_item_1, lista_poniedzialek));
#Override
public void onClick(View v) {
if(v.getId()==R.id.butPnAdd){
Intent i = new Intent(PoniedzialekActivity.this,dodawaniePoniedzialek.class);
startActivity(i);
}
}
public List<Poniedzialek> getAllPnSession() {
List<Poniedzialek> pnsessionList = new ArrayList<Poniedzialek>();
// Wybierz cale Query
String selectQuery = "SELECT * FROM " + DatabaseHelper.PN_TABLE;
dbhelper.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// petla po wszystkich rzedach & dodawanie ich do listy
if (cursor.moveToFirst()) {
do {
Poniedzialek pn = new Poniedzialek();
pn.setID(Integer.parseInt(cursor.getString(0)));
pn.setTypeOfSession(cursor.getString(1));
pn.setName(cursor.getString(2));
pn.setStartTime(cursor.getString(3));
pn.setEndTime(cursor.getString(4));
pn.setRoom(cursor.getString(5));
// Dodawanie sesji do listy
pnsessionList.add(pn);
} while (cursor.moveToNext());
}
cursor.close();
// return contact list
return pnsessionList;
}
public Cursor fetchPn() {
SQLiteDatabase db = dbhelper.getWritableDatabase();
return db.query(DatabaseHelper.PN_TABLE, new String[] {DatabaseHelper.PN_KEY_TYPE_OF_SESSION, DatabaseHelper.PN_KEY_START_TIME,
DatabaseHelper.PN_KEY_END_TIME, DatabaseHelper.PN_KEY_NAME, DatabaseHelper.PN_KEY_ROOM}, null, null, null, null, null);
}
} // end PoniedzialekActivity
This is layout_poniedzialek:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:id="#+id/butPnAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/add_pn"
/>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/tab1"
/>
<ListView
android:id="#+id/pnListView"
android:layout_width="304dp"
android:layout_height="380dp"
android:layout_gravity="center_horizontal" >
</ListView>
</LinearLayout>
E D I T
Now I keep getting an error: NullPointerException. This is what I've implemented in poniedzialekActivity ( Please note that DatabaseHelper is the name of class where I keep open/close and static final string attributes - here I am creating 5 tablets )
PoniedzialekActivity class:
public class PoniedzialekActivity extends ListActivity implements OnClickListener{
private Button butPnAdd;
private DatabaseHelper dbhelper;
private SQLiteDatabase db;
Cursor c;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_poniedzialek);
butPnAdd = (Button) findViewById(R.id.butPnAdd);
butPnAdd.setOnClickListener(this);
dbhelper = new DatabaseHelper(this);
dbhelper.open();
c = dbhelper.fetchPn();
String[] columns = new String[] { DatabaseHelper.PN_KEY_TYPE_OF_SESSION, DatabaseHelper.PN_KEY_START_TIME, DatabaseHelper.PN_KEY_END_TIME,
DatabaseHelper.PN_KEY_NAME, DatabaseHelper.PN_KEY_ROOM};
int[] to = new int[] { R.id.textSession, R.id.textStartTime, R.id.textEndTime, R.id.textName, R.id.textRoom };
new SimpleCursorAdapter(PoniedzialekActivity.this, R.layout.entry, c, columns, to);
ListView list = getListView();
list.setAdapter(new SimpleCursorAdapter(PoniedzialekActivity.this, R.layout.entry, c, columns, to));
}
#Override
public void onClick(View v) {
if(v.getId()==R.id.butPnAdd){
Intent i = new Intent(PoniedzialekActivity.this,dodawaniePoniedzialek.class);
startActivity(i);
}
}
}
DatabaseHelper.class
public class DatabaseHelper extends SQLiteOpenHelper {
private static final String DATABASE_NAME = "database.db";
private static final int DATABASE_VERSION = 1;
public static final String TAG = "ProjectDatabase";
static final String PN_TABLE = "Tablica_Poniedzialek";
static final String PN_KEY_ID = "_id";
static final String PN_KEY_TYPE_OF_SESSION ="type_of_session";
static final String PN_KEY_START_TIME ="start_time";
static final String PN_KEY_END_TIME ="end_time";
static final String PN_KEY_NAME ="name";
static final String PN_KEY_ROOM ="room";
static final String WT_TABLE = "Tablica_Wtorek";
static final String WT_KEY_ID = "_id";
static final String WT_KEY_TYPE_OF_SESSION ="type_of_session";
static final String WT_KEY_START_TIME ="start_time";
static final String WT_KEY_END_TIME ="end_time";
static final String WT_KEY_NAME ="name";
static final String WT_KEY_ROOM ="room";
static final String SR_TABLE = "Tablica_Sroda";
static final String SR_KEY_ID = "_id";
static final String SR_KEY_TYPE_OF_SESSION ="type_of_session";
static final String SR_KEY_START_TIME ="start_time";
static final String SR_KEY_END_TIME ="end_time";
static final String SR_KEY_NAME ="name";
static final String SR_KEY_ROOM ="room";
static final String CZ_TABLE = "Tablica_Czwartek";
static final String CZ_KEY_ID = "_id";
static final String CZ_KEY_TYPE_OF_SESSION ="type_of_session";
static final String CZ_KEY_START_TIME ="start_time";
static final String CZ_KEY_END_TIME ="end_time";
static final String CZ_KEY_NAME ="name";
static final String CZ_KEY_ROOM ="room";
static final String PT_TABLE = "Tablica_Piatek";
static final String PT_KEY_ID = "_id";
static final String PT_KEY_TYPE_OF_SESSION ="type_of_session";
static final String PT_KEY_START_TIME ="start_time";
static final String PT_KEY_END_TIME ="end_time";
static final String PT_KEY_NAME ="name";
static final String PT_KEY_ROOM ="room";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
private DatabaseHelper dbhelper;
private SQLiteDatabase db;
#Override
public void onCreate(SQLiteDatabase db) {
String pn_sql = "CREATE TABLE " + PN_TABLE +
"(" + PN_KEY_ID + " integer primary key autoincrement, " +
PN_KEY_TYPE_OF_SESSION + " text, " +
PN_KEY_NAME + " text, " +
PN_KEY_START_TIME + " text, " +
PN_KEY_END_TIME + " text, " +
PN_KEY_ROOM + " text);";
String wt_sql = "CREATE TABLE " + WT_TABLE +
"(" + WT_KEY_ID + " integer primary key autoincrement, " +
WT_KEY_TYPE_OF_SESSION + " text, " +
WT_KEY_NAME + " text, " +
WT_KEY_START_TIME + " text, " +
WT_KEY_END_TIME + " text, " +
WT_KEY_ROOM + " text);";
String sr_sql = "CREATE TABLE " + SR_TABLE +
"(" + SR_KEY_ID + " integer primary key autoincrement, " +
SR_KEY_TYPE_OF_SESSION + " text, " +
SR_KEY_NAME + " text, " +
SR_KEY_START_TIME + " text, " +
SR_KEY_END_TIME + " text, " +
SR_KEY_ROOM + " text);";
String cz_sql = "CREATE TABLE " + CZ_TABLE +
"(" + CZ_KEY_ID + " integer primary key autoincrement, " +
CZ_KEY_TYPE_OF_SESSION + " text, " +
CZ_KEY_NAME + " text, " +
CZ_KEY_START_TIME + " text, " +
CZ_KEY_END_TIME + " text, " +
CZ_KEY_ROOM + " text);";
String pt_sql = "CREATE TABLE " + PT_TABLE +
"(" + PT_KEY_ID + " integer primary key autoincrement, " +
PT_KEY_TYPE_OF_SESSION + " text, " +
PT_KEY_NAME + " text, " +
PT_KEY_START_TIME + " text, " +
PT_KEY_END_TIME + " text, " +
PT_KEY_ROOM + " text);";
db.execSQL(pn_sql);
db.execSQL(wt_sql);
db.execSQL(sr_sql);
db.execSQL(cz_sql);
db.execSQL(pt_sql);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w("Projekt", "aktualizacja z wersji " + oldVersion
+ " do wersji " + newVersion + " ( stare dane ulegna usunieciu ) ");
db.execSQL("DROP TABLE IF EXISTS" + PN_TABLE);
db.execSQL("DROP TABLE IF EXISTS" + WT_TABLE);
db.execSQL("DROP TABLE IF EXISTS" + SR_TABLE);
db.execSQL("DROP TABLE IF EXISTS" + CZ_TABLE);
db.execSQL("DROP TABLE IF EXISTS" + PT_TABLE);
onCreate(db);
}
public void open()
{
dbhelper.open();
}
public void close()
{
dbhelper.close();
}
public Cursor fetchPn() {
return db.query(PN_TABLE, new String[] {PN_KEY_TYPE_OF_SESSION, PN_KEY_START_TIME,
PN_KEY_END_TIME, PN_KEY_NAME, PN_KEY_ROOM}, null, null, null, null, null);
}
}
This is my MainActivity class, which holds TabHost:
public class MainActivity extends TabActivity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//--- TABHOST ---//
Resources res = getResources(); // Resource object to get Drawables
TabHost tabHost = getTabHost(); // The activity TabHost
TabHost.TabSpec spec; // Resusable TabSpec for each tab
Intent intent; // Reusable Intent for each tab
// Create an Intent to launch an Activity for the tab (to be reused)
intent = new Intent().setClass(this, PoniedzialekActivity.class);
// Initialize a TabSpec for each tab and add it to the TabHost
spec = tabHost.newTabSpec("Pn").setIndicator("Pn",
res.getDrawable(R.drawable.ic_launcher))
.setContent(intent);
tabHost.addTab(spec);
// Do the same for the other tabs
intent = new Intent().setClass(this, WtorekActivity.class);
spec = tabHost.newTabSpec("Wt").setIndicator("Wt",
res.getDrawable(R.drawable.ic_launcher))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, SrodaActivity.class);
spec = tabHost.newTabSpec("Sr").setIndicator("Sr",
res.getDrawable(R.drawable.ic_launcher))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, CzwartekActivity.class);
spec = tabHost.newTabSpec("Cz").setIndicator("Cz",
res.getDrawable(R.drawable.ic_launcher))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, PiatekActivity.class);
spec = tabHost.newTabSpec("Pt").setIndicator("Pt",
res.getDrawable(R.drawable.ic_launcher))
.setContent(intent);
tabHost.addTab(spec);
tabHost.setCurrentTab(1);
//--- END OF TABHOST ---//
}
}

setListAdapter() isn't defined for Activity... so I'm not sure how your code even compiles.
You need to inflate your layout, find the ListView using findViewById, and then set its adapter.
ListView lv = (ListView) findViewById(R.id.pnListView);
lv.setAdapter(...);

Android SQLite database not retaining it's values every time I open the Android Virtual Device

I can create the database just fine, I can Insert and view the values, but whenever I close the android virtual device in eclipse and reopen it, the database values are gone! :O
Please help me!
There are 3 classes : (1 that handles the database and 2 activities)
It would mean the world to me!!! :O
I'd +rep if I coudl
Thank you guys sooo much!#!!!
Here is my code
Database manager :`
package com.jeux;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class Database2 {
private static final String DATABASE_NAME = "JeuxMotActivity";
private static final int DATABASE_VERSION = 1;
public static final String TABLE_CATEGORIE = "Categorie";
public static final String KEY_CATEGORIE_ID_CATEGORIE = "IDCategorie";
public static final String KEY_CATEGORIE_NOM_CATEGORIE = "NomCategorie";
public static final String TABLE_MOT = "Mot";
public static final String KEY_MOT_ID_MOT = "IDMot";
public static final String KEY_MOT_MOT = "Mot";
public static final String KEY_MOT_EMAIL = "Email";
public static final String KEY_MOT_ID_CATEGORIE = "IDCategorie";
public static final String TABLE_ADMINISTRATEUR = "Administrateur";
public static final String KEY_ADMINISTRATEUR_EMAIL = "Email";
public static final String KEY_ADMINISTRATEUR_PASSWORD = "Password";
public static final String TABLE_SCORE = "Score";
public static final String KEY_SCORE_ID_JEU = "IDJeu";
public static final String KEY_SCORE_USERNAME = "Username";
public static final String KEY_SCORE_SCORE = "Score";
public static final String KEY_SCORE_INITIALES = "Initiales";
public static final String TABLE_UTILISATEUR = "Utilisateur";
public static final String KEY_UTILISATEUR_USERNAME = "Username";
public static final String KEY_UTILISATEUR_PASSWORD = "Password";
public static final String TABLE_JEU = "jeu";
public static final String KEY_JEU_ID_JEU = "IDJeu";
public static final String KEY_JEU_NOM_JEU = "NomJeu";
public static final String KEY_JEU_COMMENTAIRES = "Commentaires";
private DBHelper ourHelper;
private final Context ourContext;
private SQLiteDatabase ourDatabase;
private static class DBHelper extends SQLiteOpenHelper {
public DBHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(android.database.sqlite.SQLiteDatabase nb) {
//TODO check teh constraints and the relations
nb.execSQL("CREATE TABLE " + TABLE_CATEGORIE + " (" +
KEY_CATEGORIE_ID_CATEGORIE + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_CATEGORIE_NOM_CATEGORIE + " TEXT NOT NULL" + ");"
);
nb.execSQL("CREATE TABLE " + TABLE_MOT + " (" +
KEY_MOT_ID_MOT + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_MOT_MOT + " TEXT NOT NULL," +
KEY_MOT_EMAIL + " TEXT NOT NULL," +
KEY_MOT_ID_CATEGORIE + " TEXT NOT NULL," +
"FOREIGN KEY(" + KEY_MOT_ID_CATEGORIE + ") REFERENCES " + TABLE_CATEGORIE + "(" + KEY_CATEGORIE_ID_CATEGORIE + ")," +
"FOREIGN KEY(" + KEY_MOT_EMAIL + ") REFERENCES " + TABLE_ADMINISTRATEUR + "(" + KEY_ADMINISTRATEUR_EMAIL + ")" +
");"
);
nb.execSQL("CREATE TABLE " + TABLE_ADMINISTRATEUR + " (" +
KEY_ADMINISTRATEUR_EMAIL + " TEXT PRIMARY KEY , " +
KEY_ADMINISTRATEUR_PASSWORD + " TEXT NOT NULL" + ");"
);
nb.execSQL("CREATE TABLE " + TABLE_SCORE + " (" +
KEY_SCORE_ID_JEU + " TEXT NOT NULL, " +
KEY_SCORE_USERNAME + " TEXT NOT NULL," +
KEY_SCORE_SCORE + " INTEGER NOT NULL," +
KEY_SCORE_INITIALES + " TEXT NOT NULL," +
"FOREIGN KEY(" + KEY_SCORE_ID_JEU + ") REFERENCES " + TABLE_JEU + "(" + KEY_JEU_ID_JEU + ")," +
"FOREIGN KEY(" + KEY_SCORE_USERNAME + ") REFERENCES " + TABLE_UTILISATEUR + "(" + KEY_UTILISATEUR_USERNAME + ")" +
");"
);
nb.execSQL("CREATE TABLE " + TABLE_UTILISATEUR + " (" +
KEY_UTILISATEUR_USERNAME + " TEXT PRIMARY KEY , " +
KEY_UTILISATEUR_PASSWORD + " TEXT NOT NULL" + ");"
);
nb.execSQL("CREATE TABLE " + TABLE_JEU + " (" +
KEY_JEU_ID_JEU + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_JEU_NOM_JEU + " TEXT NOT NULL UNIQUE," +
KEY_JEU_COMMENTAIRES + " TEXT" +
");"
);
}
#Override
public void onUpgrade(android.database.sqlite.SQLiteDatabase db,
int oldversion, int newversion) {
// db.execSQL("DROP TABLE IF EXISTS " + TABLE_CATEGORIE);
// onCreate(db);
}
}
public Database2(Context c){
ourContext = c;
}
public Database2 open() throws SQLException {
ourHelper = new DBHelper(ourContext);
ourDatabase = ourHelper.getWritableDatabase();
return this;
}
public void close() throws SQLException{
ourHelper.close();
}
public long createCategorie(String name) {
ContentValues cv = new ContentValues();
cv.put(KEY_CATEGORIE_NOM_CATEGORIE, name);
return ourDatabase.insert(TABLE_CATEGORIE, null, cv);
}
public String getCategorieData(){
String result = "";
String[] columns = new String[] {KEY_CATEGORIE_ID_CATEGORIE, KEY_CATEGORIE_NOM_CATEGORIE};
Cursor c = ourDatabase.query(TABLE_CATEGORIE, columns,null, null, null, null, null);
int id = c.getColumnIndex(KEY_CATEGORIE_ID_CATEGORIE);
int name = c.getColumnIndex(KEY_CATEGORIE_NOM_CATEGORIE);
for(c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
result += c.getString(id) + " " + c.getString(name) + "\n";
}
return result;
}
}
`
Event Manager :
package com.jeux;
import android.app.Activity;
import android.app.Dialog;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class Jeuxdemots2Activity extends Activity implements OnClickListener {
Button sqlUpdate, sqlView;
EditText nameText;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
sqlUpdate = (Button) findViewById(R.id.updatebutton);
sqlView = (Button) findViewById(R.id.afficherbutton);
nameText = (EditText) findViewById(R.id.nametext);
sqlUpdate.setOnClickListener(this);
sqlView.setOnClickListener(this);
}
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
switch (arg0.getId()){
case R.id.updatebutton:
try{
String name = nameText.getText().toString();
Database2 entry = new Database2(Jeuxdemots2Activity.this);
entry.open();
entry.createCategorie(name);
entry.close();
}catch (Exception e){
String error = e.toString();
Dialog d = new Dialog(this);
d.setTitle("Dang it!");
TextView tv = new TextView(this);
tv.setText(error);
d.setContentView(tv);
d.show();
}finally{
}
break;
case R.id.afficherbutton:
Intent i = new Intent("android.intent.action.SQLVIEW");
startActivity(i);
break;
}
}
}
`
view #3 :
package com.jeux;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class SQLview extends Activity {
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.afficherlayout);
TextView tv = (TextView) findViewById(R.id.affichertextview);
Database2 info = new Database2(this);
info.open();
String data = info.getCategorieData();
info.close();
tv.setText(data);
}
}

When you close/re-open your virtual device, does it look like it's doing a full bootup every time (Shiny Android word, swipe to unlock screen, etc)? If so, it could be re-initializing everything everytime you run your application. If so, you're application and database are no longer on the device, so the data wouldn't persist.
When you create your emulator are you checking the "Snapshot" option? I believe that saves the state of your device into a file so that when you close/re-open your emulator, it's able to resume from the same point.