Develop Reference

Can't reopen table. Temporary table used twice in select query

Created a temporary table to store the subset I plan to retrieve more than once.
Here is my select query to select records from temporaryTable if the key with a different id exists in originalTable.
SELECT document
FROM originalTable
WHERE id NOT IN ( SELECT id FROM temporaryTable) AND key IN ( SELECT key FROM temporaryTable)
Any help?
I am coding in Java. Trying to avoid creating a permanent table.

I think you can use exists to make your expect.
SELECT document
FROM originalTable o
WHERE exists
(
SELECT 1
FROM temporaryTable t
WHERE t.id <> o.id AND t.key = o.key
)

Insert into SQLite database if not exist in Java [duplicate]

I have an SQLite database. I am trying to insert values (users_id, lessoninfo_id) in table bookmarks, only if both do not exist before in a row.
INSERT INTO bookmarks(users_id,lessoninfo_id)
VALUES(
(SELECT _id FROM Users WHERE User='"+$('#user_lesson').html()+"'),
(SELECT _id FROM lessoninfo
WHERE Lesson="+lesson_no+" AND cast(starttime AS int)="+Math.floor(result_set.rows.item(markerCount-1).starttime)+")
WHERE NOT EXISTS (
SELECT users_id,lessoninfo_id from bookmarks
WHERE users_id=(SELECT _id FROM Users
WHERE User='"+$('#user_lesson').html()+"') AND lessoninfo_id=(
SELECT _id FROM lessoninfo
WHERE Lesson="+lesson_no+")))
This gives an error saying:
db error near where syntax.

If you never want to have duplicates, you should declare this as a table constraint:
CREATE TABLE bookmarks(
users_id INTEGER,
lessoninfo_id INTEGER,
UNIQUE(users_id, lessoninfo_id)
);
(A primary key over both columns would have the same effect.)
It is then possible to tell the database that you want to silently ignore records that would violate such a constraint:
INSERT OR IGNORE INTO bookmarks(users_id, lessoninfo_id) VALUES(123, 456)

If you have a table called memos that has two columns id and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where text is equal to 'text to insert' and id is equal to 5, then the insert operation will be ignored.
I don't know if this will work for your particular query, but perhaps it give you a hint on how to proceed.
I would advice that you instead design your table so that no duplicates are allowed as explained in #CLs answer below.

For a unique column, use this:
INSERT OR REPLACE INTO tableName (...) values(...);
For more information, see: sqlite.org/lang_insert

insert into bookmarks (users_id, lessoninfo_id)
select 1, 167
EXCEPT
select user_id, lessoninfo_id
from bookmarks
where user_id=1
and lessoninfo_id=167;
This is the fastest way.
For some other SQL engines, you can use a Dummy table containing 1 record.
e.g:
select 1, 167 from ONE_RECORD_DUMMY_TABLE

Column not found after update db

I'm new to java . i've two questions . i'm using flyway and h2 db i added two file sql one of them to create table with two columns like that
CREATE TABLE contacts (
id bigint auto_increment NOT NULL,
name varchar(128) NOT NULL,
PRIMARY KEY(id)
);
and the other is to alter new column like that
ALTER TABLE contacts
ADD COLUMN contacts Varchar(255);
1- i used flyway.migrate worked fine but i faced mismatch so i used flyway.repair() is that normal to use it every time ?
2- when i wrote statment sql for executing insert sql command like that
stmt.execute("INSERT INTO contacts(name,contacts) VALUES('ABC','ABC#yahoo.com')");
i got
Exception in thread "main" org.h2.jdbc.JdbcSQLException: Column "CONTACTS" not found; SQL statement:
INSERT INTO contacts(name,contacts) VALUES('ABC ','ABC#yahoo.com') [42122-173]

You need to add AFTER in your second sql file.
ALTER TABLE contacts
ADD COLUMN contacts Varchar(255) AFTER name;

Referencing Surrogate keys

I have 2 tables Customers & Accounts in my Oracle Database. I have sequence numbers for generating surrogate key values for both tables.
CREATE SEQUENCE customers_seq NOCACHE;
CREATE SEQUENCE accounts_seq NOCACHE;
CREATE TABLE customers
(
customer_surrogate_id NUMBER(10),
customer_id VARCHAR2(8) UNIQUE NOT NULL,
customer_password VARCHAR2(20),
customer_name VARCHAR2(20),
customer_pan VARCHAR2(10) UNIQUE,
customer_email_id VARCHAR2(20) UNIQUE,
CONSTRAINT customer_pk
PRIMARY KEY (customer_surrogate_id)
);
CREATE TABLE accounts
(
accounts_surrogate_id NUMBER(10),
account_id VARCHAR2(10) UNIQUE NOT NULL,
customer_surrogate_id NUMBER(10),
account_type VARCHAR2(10),
account_currency VARCHAR2(20),
account_balance NUMBER(20, 2),
CONSTRAINT accounts_pk
PRIMARY KEY (accounts_surrogate_id),
CONSTRAINT accounts_fk
FOREIGN KEY (customer_surrogate_id)
REFERENCES customers(customer_surrogate_id)
);
I know how to use sequence_name.NEXTVAL & sequence_name.CURRVAL in insert statements to perform the reference
The problem is with using NEXTVAL & CURRVAL is that it assumes that inserts to both tables occur sequentially like
insert into Customers(// use NEXTVAL here)
insert into Accounts(// use CURRVAL here to reference the above row in Customers)
But in my java application, the multiple inserts for the Customers table can occur before even one insert occurs in Accounts table. CURRVAL will return the value of the last inserted row of the Customers table.
When inserting a row into Accounts table, I can get customers_id values in my application. Should the customer_id be used to query the Customers table to get the customer_surrogate_id as shown below?
insert into Customers(// use NEXTVAL here)
...
insert into Accounts(// use the customer_id to query and find customer_surrogate_id)
Is there better way to reference the Customers table in this situation?
Edit: I am using JDBC to access the database.

Simply select the value, and store it in a variable:
long customer1Id = selectNextValueFromSequence("customers_seq");
long customer2Id = selectNextValueFromSequence("customers_seq");
insertCustomerWithId(customer1Id);
insertCustomerWithId(customer2Id);
insertAccountWithCustomerId(customer1Id);
insertAccountWithCustomerId(customer2Id);

INSERT INTO SELECT STATEMENT with multiple FK

This is my code with 1 FK.
here's the columns
([PK]charityRoomID, charityRoomStatus, [FK]charityWardID)
INSERT INTO tbl_addcharityroom1 (charityRoomStatus, charityWardID)
VALUES ('"+jTextField10aw.getText() +"', (
select charityWardID
from tbl_addcharityward
where diseaseCategory='"+ jComboBox1.getSelectedItem().toString() +"'))";
Now, I added a new column(RateID) which is another FK, but i don't know the correct statement for multiple FK. here's the columns
([PK]charityWardID, charityRoomStatus, [FK]charityWardID, [FK]rateID)
I am using netbeans & mySQL

A FK is just a constraint on a database column. It basically means that your column content must map to a specified column when you insert data.
So, if your insert statement specifies a value that exist in the ID column of your Rate table, everything will be allright. Otherwise, an exception will occur.
Basically you just need to do this, replacing "yourRateIdValue" by an Id that actually exist in your Rate table:
"INSERT INTO tbl_addcharityroom1 (charityRoomStatus, charityWardID, rateID)
VALUES ('" + jTextField10aw.getText() + "', (
select charityWardID
from tbl_addcharityward
where diseaseCategory='"+ jComboBox1.getSelectedItem().toString() +"'), yourRateIdValue)";
You can also replace the "yourRateIdValue" by a select statement, as you did for the "charityWardID" column