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java postgresql using trigger

SQL = "create view CSaccept as select sID, cName from Apply where major = 'CS' and decision = 'Y' ";
stmt.executeUpdate(SQL);
SQL = "create or replace function test1() returns trigger as $$\n" +
"begin\n" +
" update Apply set cName = New.cName where (sID = Old.sID and cName = Old.cName and Apply.major = 'CS' and Apply.decision = 'Y');\n" +
" return Old;\n" +
"end;\n" +
"$$\n" +
"language 'plpgsql';\n" +
"create trigger CSacceptUpdate\n" +
"instead of update of cName on CSaccept\n" +
"for each row\n" +
"execute procedure test1();";
stmt.executeUpdate(SQL);
Hi I am writing a program in java using postgresql, and the error like below keeps popping up in the above SQL statement. What is the problem?
Exception in thread "main" org.postgresql.util.PSQLException: ERROR: INSTEAD OF triggers cannot have column lists
at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2553)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2285)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:323)
at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:473)
at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:393)
at org.postgresql.jdbc.PgStatement.executeWithFlags(PgStatement.java:322)
at org.postgresql.jdbc.PgStatement.executeCachedSql(PgStatement.java:308)
at org.postgresql.jdbc.PgStatement.executeWithFlags(PgStatement.java:284)
at org.postgresql.jdbc.PgStatement.executeUpdate(PgStatement.java:258)
at SqlTest2.main(SqlTest2.java:270)
SQL = "create or replace function test2() returns trigger as $$\n" +
"begin\n" +
" delete from Apply where sID = old.sID and cName = old.cName and major = 'CS' and decision = 'Y';\n" +
" return Old;\n" +
"end;\n" +
"$$\n" +
"language 'plpgsql';\n" +
"create trigger CSacceptDelete\n" +
"instead of delete on CSaccept\n" +
"for each row\n" +
"execute procedure test2();";
above one works well. I don't know why First one is not working.

"ORA-01858: a non-numeric character was found where a numeric was expected" when writing a query in a java class

I have a web application where 3 inputs are taken from the user and after clicking search button results are displayed. The three inputs are; id (not unique), startdate and enddate. I want to be able to get the results in these situations: If the user enters
only id
only start date (enrolldate in db table)
only end date (graduationdate in db table)
id and start date
when all the fields entered together
In my StudentManager.java class I have a SQL string like below;
final String SQL_STU = " select "
+ " t.name,"
+ " t.surname, "
+ " t.lecture,"
+ " from studenttable t "
+ " where t.school = 'CHC' "
+ " and t.id = case when '" + studentInfo.getID() + "'" +" is null then t.id else '" + studentInfo.getID() + "' end "
+ " and t.enrolldate >= case when '" + studentInfo.getStartDate() + "' is null then t.enrolldate else to_date('"
+ studentInfo.getStartDate() + "', 'DD.MM.YYYY HH24:MI:SS') end "
+ " and t.graduationdate >= case when '" + studentInfo.getEndDate() + "' is null then t.graduationdate else to_date('"
+ studentInfo.getEndDate() + "', 'DD.MM.YYYY HH24:MI:SS') end " ;
I will execute this query and get the results into a result set.
I have a couple of problems with this code; for example when I comment out this part:
+ " and t.enrolldate >= case when '" + studentInfo.getStartDate() + "' is null then t.enrolldate else to_date('"
+ studentInfo.getStartDate() + "', 'DD.MM.YYYY HH24:MI:SS') end "
+ " and t.graduationdate >= case when '" + studentInfo.getEndDate() + "' is null then t.graduationdate else to_date('"
+ studentInfo.getEndDate() + "', 'DD.MM.YYYY HH24:MI:SS') end " ;
It works without errors but when I give all the inputs null (id, date1, date2) it displays nothing. Shouldn't it display all the results since there is no specific id? (User will not be able to submit 3 empty fields but I am curious why it does not work like the way I mentioned? )
The other thing is when I execute the whole code (with to_date parts) it gives the error in the title. But it does not give any error when I execute like this:
final String SQL_STU = " select "
+ " t.name,"
+ " t.surname, "
+ " t.lecture,"
+ " from studenttable t "
+ " where t.school = 'CHC' "
+ " and t.enrolldate >= case when '" + studentInfo.getStartDate() + "' is null then t.enrolldate else to_date('"
+ studentInfo.getStartDate() + "', 'DD.MM.YYYY HH24:MI:SS') end " ;
So in summary I couldn't write the query the way I wanted. I am not that experienced with queries. If you know any better way you can also suggest it since I have come to a dead end. I also tried something with NVL but I could not make it work also.
Notes:
ID, StartDate,EndDate are type string in my StudentInfo.java class
id is type varchar and dates are type date in database table.(PL/SQL)

The best answer to your question is to use a prepared statement:
String sql = "SELECT t.name, t.surname, t.lecture ";
sql += "FROM studenttable t ";
sql += "WHERE t.school = 'CHC' AND "
sql += "t.id = COALESCE(?, t.id) AND ";
sql += "t.entrolldate >= COALESCE(?, t.enrolldate) AND ";
sql += "t.graduationdate >= COALESCE(?, t.graduationdate)";
PreparedStatement ps = conn.prepareStatement(sql);
ps.setInt(1, studentInfo.getID());
ps.setDate(2, studentInfo.getStartDate());
ps.setDate(3, studentInfo.getEndDate());
ResultSet rs = ps.executeQuery();
while (rs.next()) {
// process a row
}
The reason why using a statement is preferred is that it frees you from having to manually marshal your Java date (and other type) variables into your Oracle SQL statement. Instead, the above code lets the JDBC driver worry about how to convert a Java date variable to the correct format in the actual SQL code. Also, statements allow you to write a SQL query with minimal concatenations, which reduces the chances for error and typos.
Note that you might have to call a setter other than PreparedStatement#setDate depending on the what getStartDate() and getEndDate() methods actually return in your Java code.

misuse of aggregate function SUM()

I want to insert the SUM of Somme_versee (column in table Versement) in the column Versement_total.
This is a part of my code:
statement.executeUpdate("INSERT INTO Versement ( Nom , Prenom, Date , Somme_versee,Prix_du_logement, Nom_du_projet) VALUES('" + nom.getText() +"','" +prenom.getText() +"','" +date.getText() + "'," + verse.getText() + ", " + "(SELECT Prix_du_logement FROM Client WHERE Nom='"+ nom.getText() +"' AND Prenom='"+ prenom.getText() + "')," + " (SELECT Nom_du_projet FROM Client WHERE Nom='" + nom.getText()+ "' AND Prenom='" +prenom.getText() + "'))");
statement.executeUpdate("UPDATE Versement SET Versement_total= SUM(Somme_versee) " );
When executing I get this error: misuse of aggregate function SUM()

You should never do this in the same table. And it will get worse when the table gets more records. But what you seem to want is:
UPDATE Versement SET Versement_total = (SELECT SUM(Somme_versee) FROM Versement)

How to retrieve a data between dates

I have 2 tables. A booking table and a room table. In the booking table I have the following columns: BookingID StartDate EndDate CustomerID RoomID
In the Room table I have the following columns: RoomID RoomSize
I am creating a booking system. I want to be able to query the database where I am able to get a list of rooms that are booked between 2 dates which are also based on size (small, medium or large) types.
E.g. if user clicks on small room and enters dates between 2010-02-02 to 2010-02-25 then 4 should appear as my database contains 4 small rooms that are booked between those dates.
This is what I have so far:
String sqlStatement = "select RoomID from Booking where RoomID in (select Room.RoomID from Room where Room.RoomSize is " + type + ") AND ((Booking.StartDate between "+ startD +" AND " + endD + ") OR (Booking.EndDate between "+ startD + " AND " + endD + "))";
This is the error I am getting:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'Medium) AND ((Booking.StartDate between 2016-02-09 AND 2016-02-09) OR (Booking.E' at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
I am new to SQL and having trouble doing this. Also, is my logic right?
startD and endD represents the dates that the user has entered and typeOfRoom represent the type of the room the user wants to book; e.g. eithier Small, Medium or Large

Do not use string concatenation to insert user-supplied values into SQL, especially for strings. It will leave you open to SQL Injection attacks, and SQL syntax issues. Use a PreparedStatement.
Also, replace is with =.
String sql = "select RoomID" +
" from Booking" +
" where RoomID in (" +
"select Room.RoomID" +
" from Room" +
" where Room.RoomSize = ?" +
")" +
" and ((Booking.StartDate between ? AND ?)" +
" or (Booking.EndDate between ? AND ?))";
try (PreparedStatement stmt = conn.prepareStatement(sql)) {
stmt.setString(1, type);
stmt.setDate (2, startD);
stmt.setDate (3, endD);
stmt.setDate (4, startD);
stmt.setDate (5, endD);
try (ResultSet rs = stmt.executeQuery()) {
while (rs.next()) {
// code here
}
}
}

The date handling look ok I think, but you need to quote the type string in the statement. And you should not use is, just use normal =
String sqlStatement = "select RoomID from Booking where RoomID in (select Room.RoomID from Room where Room.RoomSize = '" + type + "') AND ((Booking.StartDate between "+ startD +" AND " + endD + ") OR (Booking.EndDate between "+ startD + " AND " + endD + "))";

Can you try if this statement works? I have replaced the 'is' keyword with '=' operator and put all the variables between "".
String sqlStatement = "select RoomID from Booking where RoomID in (select Room.RoomID from Room where Room.RoomSize = \"" + type + "\") AND ((Booking.StartDate between \""+ startD +"\" AND \"" + endD + "\") OR (Booking.EndDate between \""+ startD + "\" AND \"" + endD + "\"))";

Unable to insert record in MySql using JAVA

I am new to Java and MYSql in fact using this combination first time and facing real trouble. I want to insert few records in a table but unable to do so. Following are the fields and datatype in the table named tbl_cdr in MySql.
**Field** **Type**
DATEANDTIME datetime NULL
VALUE1 int(50) NULL
VALUE2 varchar(50) NULL
VALUE3 varchar(50) NULL
VALUE4 varchar(50) NULL
VALUE5 varchar(50) NULL
The record I want to insert contains following values
2014-05-19 02:37:18, 405, MGW190514023718eab4, 923016313475, IN, ALERTSC
I am using following query and statements to Insert record in table
sqlQuery = "INSERT INTO tbl_cdr (DATEANDTIME,VALUE1,VALUE2,VALUE3,VALUE4,VALUE5)" + "VALUES ("+ forDateAndTime.format(date) + ", " + columnsList.get(1) + ", " + columnsList.get(2) + ", " + columnsList.get(3) + ", " + columnsList.get(4) + ", " + columnsList.get(5) + ")";
try
{
Statement qryStatement = conn.createStatement();
qryStatement.executeUpdate(sqlQuery);
qryStatement.close();
} catch (SQLException ex)
{
Logger.getLogger(CdrProject.class.getName()).log(Level.SEVERE, null, ex);
}
But when I reach the statement qryStatement.executeUpdate(sqlQuery); exception is thrown as:
MySQLSyntaxErrorException: You have an error in your SQL syntax;
check the manual that corresponds to your MySQL server version for the
right syntax to use near '02:37:18, 405, MGW190514023718eab4,
923016313475, IN, ALERTSC)' at line 1

value2 ,value3 ,value4 and value 5 are varchars so it should be written within ''.
Do like this
sqlQuery = "INSERT INTO tbl_cdr (DATEANDTIME,VALUE1,VALUE2,VALUE3,VALUE4,VALUE5)" + "VALUES ("+ forDateAndTime.format(date) + ", " + columnsList.get(1) + ", '" + columnsList.get(2) + "',' " + columnsList.get(3) + "',' " + columnsList.get(4) + "',' " + columnsList.get(5) + "')";

You're inserting the date incorrectly. MySQL allows you to insert a string literal or a number.
You're trying to use 02:37:18 as a number, when really you should be using it as a string literal: '02:37:18'
Here is the MySql Reference describing this.
You're also not treating your varchars as strings either, they should be enclosed with quotes.