What is the difference between DISTINCT and GROUP BY? They usually produce the same plan. Use GROUP BY for aggregates and DISTINCT to remove duplicates.
SQL SERVER – Fix : Error 701 There is insufficient system memory to run this query
For Error 701, insufficient system memory, compare max server memory with min server memory, check the paging file size, and free caches with DBCC commands.
SQL SERVER – @@IDENTITY vs SCOPE_IDENTITY() vs IDENT_CURRENT – Retrieve Last Inserted Identity of Record
@@IDENTITY vs SCOPE_IDENTITY() vs IDENT_CURRENT: how each one returns the last identity value, and why a trigger can make @@IDENTITY give the wrong one.
SQL SERVER – Stored Procedure – Clean Cache and Clean Buffer
DBCC FREEPROCCACHE will invalidate all stored procedure plans that the optimizer has cached in memory. Let us learn how to clean cache.
SQL SERVER – Fix: Error Msg 128 The name is not permitted in this context. Only constants, expressions, or variables allowed here. Column names are not permitted.
Msg 128, The name is not permitted in this context, shows up when one column is used as the DEFAULT of another. Use only constants, expressions or variables.
SQL SERVER – SQL Commandments – Suggestions, Tips, Tricks
My 20 SQL Commandments for SQL Server, rewritten from an Oracle article: know your data, test with realistic data, write identical statements, and more tips.
SQL SERVER – DBCC command to RESEED Table Identity Value – Reset Table Identity
DBCC CHECKIDENT with RESEED lets you reset table identity to any value. Reseed to 0 so the next insert gets 1, and never go below values already in the table.