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When do you use transactions in SQL Server?
Transactions are usually used when you have CREATE, UPDATE or DELETE statements and you want to have the atomic behavior, that is, Either commit everything or commit nothing. Make sure nobody else could update the table of interest while the bunch of your select query is executing. Have a look at this msdn post.
What happens if I delete multiple rows in SQL?
If the DELETE removes multiple rows, and any one of the removed rows violates a trigger or constraint, the statement is canceled, an error is returned, and no rows are removed.
How does a DELETE statement in SQL Server work?
By default, a DELETE statement always acquires an intent exclusive (IX) lock on the table object it modifies, and holds that lock until the transaction completes. With an intent exclusive (IX) lock, no other transactions can modify data; read operations can take place only with the use of the NOLOCK hint or read uncommitted isolation level.
Can a SELECT statement outside of a transaction?
I got one answer that…. SELECT inside the transaction can see changes made by other previous Insert/Update/Delete statements in that transaction, a SELECT statement outside the transaction cannot. Above statement is it true or not ?
Can a select outside a transaction see the transaction?
If you’re using the default isolation level (READ COMMITTED) – then yes – a SELECT outside the transaction will not see any insert or updates a transaction has made, until those are actually committed.
Why does begin transaction with while loop in TSQL?
This query never finishes perhaps because it stops and look for COMMIT TRANSACTION after inserting one row (when @cnt = 1) but I don’t want to COMMIT TRANSACTION because I want to see results before committing.
What happens if SELECT statement is inside explicit transaction?
If the single SELECT statement is inside an explicit transaction without altering the isolation levels, I’m pretty sure that will have no effect at all. Individual statements are, by themselves, transactions that are auto-committed or rolled back on error.