Let’s say that you have a table (shown below) and you want to select rows where column Name contains a percentage sign. So in this case query should return rows with ids: 3, 5 and 6.
If you are going to use the following query:
SELECT [Id], [Name] FROM [Items] WHERE [Name] LIKE '%'
you will receive all rows from your table because in this case % is wildcard character that means any string of zero or more characters.
To fulfill our requirements we can use followings queries:
1) we can use [] wildcard character
SELECT [Id], [Name] FROM [Items] WHERE [Name] LIKE '%[%]%'
2) we can define escape character in query - the escape character has no default and must contain only one character
SELECT [Id], [Name] FROM [Items] WHERE [Name] LIKE '%\%%' ESCAPE '\'
Notice that in the above queries the first and the last percent character is a wildcard that matches zero or more of any character.