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Building Regular Expressions

In this section are the elements and rules for building SQL regular expressions.

Characters

Within regular expressions, most characters represent themselves.The only exceptions are the special characters below:

[ ] ( ) | ^ - + * % _ ? { }

... and the escape character, if it is defined.

A regular expression that contains no special characters or escape characters matches only strings that are identical to itself (subject to the collation in use).That is, it functions just like the ‘=’ operator:

'Apple' similar to 'Apple'  -- true
'Apples' similar to 'Apple' -- false
'Apple' similar to 'Apples' -- false
'APPLE' similar to 'Apple'  -- depends on collation