You can use RETURNING clause: DELETE FROM table WHERE condition IS TRUE RETURNING *; After that you just have to check number of rows returned. You can streamline it with CTE: WITH deleted AS (DELETE FROM table WHERE condition IS TRUE RETURNING *) SELECT count(*) FROM deleted; This should return just the number of deleted … Read more
simply use DELETE FROM test WHERE 1= 1 LIMIT 10
The error means that you have data in other tables that references the data you are trying to delete. You would need to either drop and recreate the constraints or delete the data that the Foreign Key references. Suppose you have the following tables dbo.Students ( StudentId StudentName StudentTypeId ) dbo.StudentTypes ( StudentTypeId StudentType ) … Read more
TRUNCATE doesn’t generate any rollback data, which makes it lightning fast. It just deallocates the data pages used by the table. However, if you are in a transaction and want the ability to “undo” this delete, you need to use DELETE FROM, which gives the ability to rollback. EDIT: Note that the above is incorrect … Read more
EntityManager#remove() works only on entities which are managed in the current transaction/context. In your case, you’re retrieving the entity in an earlier transaction, storing it in the HTTP session and then attempting to remove it in a different transaction/context. This just won’t work. You need to check if the entity is managed by EntityManager#contains() and … Read more
Due to the locking implementation issues, MySQL does not allow referencing the affected table with DELETE or UPDATE. You need to make a JOIN here instead: DELETE gc.* FROM guide_category AS gc LEFT JOIN guide AS g ON g.id_guide = gc.id_guide WHERE g.title IS NULL or just use a NOT IN: DELETE FROM guide_category AS … Read more
As of Hive version 0.14.0: INSERT…VALUES, UPDATE, and DELETE are now available with full ACID support. INSERT … VALUES Syntax: INSERT INTO TABLE tablename [PARTITION (partcol1[=val1], partcol2[=val2] …)] VALUES values_row [, values_row …] Where values_row is: ( value [, value …] ) where a value is either null or any valid SQL literal UPDATE Syntax: … Read more
The best way is to use IN statement : DELETE from tablename WHERE id IN (1,2,3,…,254); You can also use BETWEEN if you have consecutive IDs : DELETE from tablename WHERE id BETWEEN 1 AND 254; You can of course limit for some IDs using other WHERE clause : DELETE from tablename WHERE id BETWEEN … Read more
A bit too late with this answer, but since I faced a similar question, I made a test with JMeter and a MySQL server on same machine, where I have used: A transaction Controller (generating parent sample) that contained two JDBC Requests: a Delete and an Insert statement A sepparate JDBC Request containing the Update … Read more
It all depends … Assuming no concurrent write access to involved tables or you may have to lock tables exclusively or this route may not be for you at all. Delete all indexes (possibly except the ones needed for the delete itself). Recreate them afterwards. That’s typically much faster than incremental updates to indexes. Check … Read more