Updating multiple tables in sql

The SQL Transport Schema Generation Wizard does not permit the selection of multiple tables for updating when generating a schema for an updategram.

It is possible, however, to manually create an updategram that will update multiple tables.

There are two ways to modify a table using information contained in other tables in the database: using sub-selects, or specifying additional tables in the you should ensure that the join produces at most one output row for each row to be modified.

In other words, a target row shouldn't join to more than one row from the other table(s).

To do this without failing the entire transaction, use savepoints: BEGIN; -- other operations SAVEPOINT sp1; INSERT INTO wines VALUES('Chateau Lafite 2003', '24'); -- Assume the above fails because of a unique key violation, -- so now we issue these commands: ROLLBACK TO sp1; UPDATE wines SET stock = stock 24 WHERE winename = 'Chateau Lafite 2003'; -- continue with other operations, and eventually COMMIT; If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.

This dictionary provides a list of argument names accepted by various schema-level constructs on behalf of a dialect.

But if there are a large number of rows that require an update, then the overhead of issuing large numbers of UPDATE statements can result in the operation as a whole taking a long time to complete. ORG_ID = @ORG_ID COMMIT BEGIN TRANSACTION is not the same as BEGIN which starts a block ( used in IF for example).And I agree about the hack-i-ness of the suggested link (I might even suggest removing it).A more effective solution to this problem is to attempt to reduce the number of UPDATE statements.Let us start with a simple table: UPDATE staff SET salary = 1200 WHERE name = ' Bob'; UPDATE staff SET salary = 1200 WHERE name = ' Jane'; UPDATE staff SET salary = 1200 WHERE name = ' Frank'; UPDATE staff SET salary = 1200 WHERE name = ' Susan'; UPDATE staff SET salary = 1200 WHERE name = ' John'; UPDATE staff SET salary = 1200 WHERE name = ' Bob'; UPDATE staff SET salary = 1250 WHERE name = ' Jane'; UPDATE staff SET salary = 1200 WHERE name = ' Frank'; UPDATE staff SET salary = 1250 WHERE name = ' Susan'; UPDATE staff SET salary = 1200 WHERE name = ' John'; We are no longer setting all the salary fields to the same value, so we can’t collapse it into a single statement.

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If it does, then only one of the join rows will be used to update the target row, but which one will be used is not readily predictable.

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