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 …
How do I perform an IF...THEN in an SQL SELECT?
15 MFómh 2008 · The CASE statement is the closest to IF in SQL and is supported on all versions of SQL Server.
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 - Copy data into another table - Stack Overflow
How to copy/append data from one table into another table with same schema in SQL Server? Edit: let's say there is a query select * into table1 from table2 where 1=1 which creates table1 wi...
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 …
SQL to find the number of distinct values in a column
5 Aib 2019 · SQL to find the number of distinct values in a column Asked 17 years, 3 months ago Modified 2 years, 9 months ago Viewed 826k times
sorting - SQL multiple column ordering - Stack Overflow
12 Ean 2010 · How can I sort multiple columns in SQL and in different directions? For instance, 'column1' would be sorted descendingly and 'column2' ascendingly.
sql - What is the difference between JOIN and INNER JOIN
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 …
Remove all spaces from a string in SQL Server - Stack Overflow
3 Beal 2012 · What is the best way to remove all spaces from a string in SQL Server 2008? LTRIM(RTRIM(' a b ')) would remove all spaces at the right and left of the string, but I also need …
sql - Delete duplicate rows keeping the first row - Stack Overflow
10 To delete the duplicate rows from the table in SQL Server, you follow these steps: Find duplicate rows using GROUP BY clause or ROW_NUMBER () function. Use DELETE statement to …
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