sql - NOT IN vs NOT EXISTS - Stack Overflow
Which of these queries is the faster? NOT EXISTS: SELECT ProductID, ProductName FROM Northwind..Products p WHERE NOT EXISTS ( SELECT 1 FROM Northwind..[Order Details] od …
Should I use != or <> for not equal in T-SQL? - Stack Overflow
Yes; Microsoft themselves recommend using <> over != specifically for ANSI compliance, e.g. in Microsoft Press training kit for 70-461 exam, "Querying Microsoft SQL Server", they say "As an …
What does the "@" symbol do in SQL? - Stack Overflow
The @CustID means it's a parameter that you will supply a value for later in your code. This is the best way of protecting against SQL injection. Create your query using parameters, rather than …
How do I perform an IF...THEN in an SQL SELECT?
Sep 15, 2008 · The CASE statement is the closest to IF in SQL and is supported on all versions of SQL Server.
SQL: IF clause within WHERE clause - Stack Overflow
Sep 18, 2008 · Is it possible to use an IF clause within a WHERE clause in MS SQL? Example: WHERE IF IsNumeric(@OrderNumber) = 1 OrderNumber = @OrderNumber ELSE OrderNumber LIKE '%' + @
SQL to find the number of distinct values in a column
Apr 5, 2019 · SQL to find the number of distinct values in a column Asked 17 years, 2 months ago Modified 2 years, 7 months ago Viewed 826k times
sql - Concatenate text from multiple rows into a single text string ...
Consider a database table holding names, with three rows: Peter Paul Mary Is there an easy way to turn this into a single string of Peter, Paul, Mary?
sql - What is the difference between JOIN and INNER JOIN ... - Stack ...
SELECT * FROM table INNER JOIN otherTable ON table.ID = otherTable.FK Is there any difference between the statements in performance or otherwise? Does it differ between different SQL …
SQL: How to properly check if a record exists - Stack Overflow
Nov 23, 2010 · While reading some SQL Tuning-related documentation, I found this: SELECT COUNT(*) : Counts the number of rows. Often is improperly used to verify the existence of a record. …
sql - Selecting COUNT (*) with DISTINCT - Stack Overflow
In SQL Server 2005 I have a table cm_production that lists all the code that's been put into production. The table has a ticket_number, program_type, program_name and push_number along with some ot...