Cursor for updating table in sql oracle Free sex text chat room no email

The FOR UPDATE clause in the SELECT statement can only be specified in the top level; subqueries cannot have this clause.

Another Example of WHERE CURRENT OF Go through all Maths students and set all GPA’s under 4.0 to 4.0!

Inside a cursor loop, WHERE CURRENT OF allows the current row to be directly updated.The interesting thing about this method is that it performs a context-switch between PL/SQL and SQL for every FETCH; this is less efficient.I include it here because it allows us to compare the cost of context-switches to the cost of updates.I have one table A has column (id, field_1,field_2), and another table B has column (id,field_2) Now I want to merge table B to A, that means i want to update field_2 in table A to value of table B. BTW I am using oracle Thanks Now, each time the above is executed, it will do it across all rows in the table.If this is something you need to do all the time, I would suggest something else, but for a one-off or very small tables it should be sufficient.DECLARE CURSOR c1 IS SELECT * FROM test6; rec_cur c1%rowtype; BEGIN OPEN c1; LOOP FETCH c1 INTO rec_cur; EXIT WHEN c1%notfound; UPDATE test SET fk = rec_, fill = rec_WHERE pk =; END LOOP; CLOSE C1; END; / This is the simplest PL/SQL method and very common in hand-coded PL/SQL applications.Update-wise, it looks as though it should perform the same as the Explicit Cursor Loop.Now I need to update one column, namely store_id, to make it a primary column with unique number id.Since there were a lot of duplicate data in this column, the best way to do is to update this column with the sequence numbers.You could create a trigger on table B that updates table A every time field_2 on table B is updated.I have a Oracle database table with some fields (columns) in numeric format.

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