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When to use a loop and delete rows?
Use a loop combined with TOP and delete rows in smaller transactions. Here are a couple of variations of the same thing. Note that I have arbitrarily chosen 1000 as a figure for demonstration purposes. view source print?
How to do a while loop in SQL Server?
Here’s a homemade do-while loop, since SQL Server doesn’t have one built in. When I delete in batch I add a WAITFOR DELAY (at least 1 or 2 seconds). Also the first statement I created outside the loop. Btw, avoid using ROWCOUNT as delimiter ( https://docs.microsoft.com/en-us/sql/t-sql/statements/set-rowcount-transact-sql?view=sql-server-2017 ).
Why is deleting a lot of rows so slow?
Deleting a lot of rows can be very slow. Try to delete a few at a time, like: Check with the help of SQL Profiler for the root cause of this issue. There may be Triggers causing the delay in Execution. It can be anything.
Why is SQL Server Delete statement in SQL so slow?
After inspecting an SSIS Package (due to a SQL Server executing commands really slow), that was set up in a client of ours about 5-4 years before the time of me writing this, I found out that there were the below tasks: 1) insert data from an XML file into a table called [Importbarcdes].
How to delete rows based on rowcount in SQL Server?
In SQL Server, I ran I to problems with the delete statement locking the table, and also taking a long time to execute. All the deleted records have to go into the transaction log. What worked better was to select the records I wanted to keep into a new table, and then rename the tables.
When to use a for loop in Excel?
If your loop runs from 6 to the last row deleting rows along the way, your For loop index will get out of sync with the row numbers in your sheet after the first deletion. This is what happens when your For loop starts at the top and works down… you will probably miss bad rows!
How many rows should be in a while loop?
I put 10’000 rows in my TEST table. In the end the counter should be 9 and at the end of the loop the table should contain 1000 rows, but in my case the counter is 11 and the table is empty. Why doesn’t it work?