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How to bulk delete records using temporary tables in Hibernate?

I have a question. Where did these methods go?
Dialect.supportsTemporaryTables();
Dialect.generateTemporaryTableName();
Dialect.dropTemporaryTableAfterUse();
Dialect.getDropTemporaryTableString();
I've tried to browse git history for Dialect.java, but no luck. I found that something like
MultiTableBulkIdStrategy was created but I couldn't find any example of how to use it.
To the point...I have legacy code (using hibernate 4.3.11) which is doing batch delete from
multiple tables using temporary table. In those tables there may be 1000 rows, but also there may
be 10 milion rows. So just to make sure I don't kill DB with some crazy delete I create temp table where I put (using select query with some condition) 1000 ids at once
and then use this temp table to delete data from 4 tables. It's running in while cycle until all data based on some condition is not deleted.
Transaction is commited after each cycle.
To make it more complicated this code has to run on top of: mysql, mariadb, oracle, postgresql, sqlserver and h2.
It was done using native SQL, with methods mentioned above. But not I can't find a way how
to refactor it.
My first try was to create query using nested select like this:
delete from TABLE where id in (select id from TABLE where CONDITION limit 1000) but this is way slower as I have to run select query multiple times for each delete and limit is not supported in nested select in HQL.
Any ideas or pointers?
Thanks.

The methods were present in version 4.3.11 but removed in version 5.0.0. It seems a bit unusual that they were removed rather than deprecated - the background is on this Jira ticket.
To quote from this:
Long term, I think the best approach is to remove the Dialect method
intended to support table tabled in a piecemeal fashion and to make
MultiTableBulkIdStrategy be a fully self-contained contract.
The methods were removed in this commit.
So it seems that getDefaultMultiTableBulkIdStrategy() is the intended replacement for these methods - but I'm not entirely clear on how, as it currently has no Javadoc. Guess you could try to work it out from the source code ...or if all else fails, perhaps try to contact Steve Ebersole, who implemented the change?

Huge Update or Inserts into DB2 using JAVA and JPA 1.0

I have a JAVA requirement where i have 1500 records that I have to update or insert into the database.
If a record exists with userId, then update it.
If a record does not exist with userId, then Insert it.
And, if there is an error in lets say, 10th record,,,I need to get
the error code for that record.
It looks like I have 2 options using JPA 1.0
A) Fire a select to check if record exists. If yes, then fire update. If not, fire insert.
B) Fire an insert always,,,but i get an uniqe record exception, only then fire an update query..
Are there any other more efficient ways ? how can this be done with as few queries and as quick as possible ?
ENV- JAVA, JPA 1.0, DB2

You did not specify which version of DB2 you use and on which system. Anyway, check if MERGE statement is available on your DB:
LUW from 9.5.0: http://www.ibm.com/support/knowledgecenter/SSEPGG_9.5.0/com.ibm.db2.luw.sql.ref.doc/doc/r0010873.html
Z/OS from 10.0.0: http://www.ibm.com/support/knowledgecenter/SSEPEK_10.0.0/sqlref/src/tpc/db2z_sql_merge.html
Another way is to do delete + insert on every record (poor performance).
Third option is to create dynamic one delete statement with listed ID/KEY in where clause from data you are going to update, fire delete and then insert all data.
Performance of every option will depend on table specification, indexes etc.

you can write query in mysql as below
//suppose a as pk
INSERT INTO table (a,b,c) VALUES (1,2,3)
ON DUPLICATE KEY UPDATE c=c+1,b=b+1;
here update will run when record with pk as a=1 is already present
refer below link http://dev.mysql.com/doc/refman/5.7/en/insert-on-duplicate.html

Increasing INSERT speed

I'm currently using the following query to insert into a table only if the record does not already exist, presumably this leads to a table scan. It inserts 28000 records in 10 minutes:
INSERT INTO tblExample(column)
(SELECT ? FROM tblExample WHERE column=? HAVING COUNT(*)=0)
If I change the query to the following, I can insert 98000 records in 10 minutes:
INSERT INTO tblExample(column) VALUES (?)
But it will not be checking whether the record already exists.
Could anyone suggest another way of querying such that my insert speed is faster?

One simple solution (but not recommended) could be to simply have insert statement, catch duplicate key exception and log them. Assuming that the table has unique key constraint.

Make sure that you have an index on the column[s] you're checking. In general, have a look at the query execution plan that the database is using - this should tell you where the time is going, and so what to do about it.
For Derby db this is how you get a plan and how to read it.
Derby also has a merge command, which can act as insert-if-not-there. I've not used it myself, so you'd need to test it to see if it's faster for your circumstances.

Using INSERT INTO & UPDATE at the same time - JAVA SQL

I have a question.
So I have a add functionality where the user can add cars to the database. How do I do a check whilst adding the car, so that if the car does exist-the data is overwritten, instead of an error messaging like 'Duplicate error' appearing?
So I have...
INSERT INTO Cars VALUES (1, "AUDI R8", 10);
How do I do it so that if a user inputs (1, "BMW X5, 15), it overwrites the current data?
How would I have an INSERT INTO and UPDATE STATEMENT at the same time? Also how do I make use of transactions here?
Many thanks

MySQL has a REPLACE statement for this kind of cases:
REPLACE works exactly like INSERT, except that if an old row in the table has the same value as a new row for a PRIMARY KEY or a UNIQUE index, the old row is deleted before the new row is inserted [...]REPLACE is a MySQL extension to the SQL standard. It either inserts, or deletes and inserts.
Check the reference for the REPLACE statement.

Well, the best solution for this problem are the TRIGGERS.
Triggers allow you to separate the application layer from the the database.
In your case you need to launch an error, so this is a trigger called "passive", that reacts automatically only if the condition is violated.
Take a look a this: https://dev.mysql.com/doc/refman/5.0/en/trigger-syntax.html or various related docs.

Maybe is not the best solution, but u can do a SELECT first, and after do an UPDATE or a simply INSERT, depends of the case.

Sqlite not allow WHERE clause

I am developing one app in which i have make sqlite Database.so there are one table with 3 Field
1._id
2.Appname
3.Rating
For this I need to set Data in Last Field(Rating) with condition where _id = 1 like this...
but from Post I found that Sqlite not allow where clauses so how can I do this?
INSERT INTO Packageinformation(appRating)VALUES (3) where _id=1;
can you please help me out this.

You have to use update, not insert.

Perhaps that's what you need:
UPDATE Packageinformation SET appRating = 3 WHERE _id = 1;

INSERT INTO inserts data into the database, a WHERE clause is only used for SELECT, which is reading rows.
INSERT INTO with a WHERE clause is nonsense.
If you want to update a row, use UPDATE (see documentation for details).
You could also use REPLACE INTO, but be careful because it might set all other fields to their default values.