POSTGRESQL REGEX HOW TO

Since the number of characters to be extracted was not specified, the extraction ran to the end of the string. Let us extract 99 from the string Guru99: SELECT substring('Guru99' from 5) We specified that the extraction of the substring should begin from position 1, and 4 characters should be extracted.

POSTGRESQL REGEX HOW TO

The following example shows how to specify the starting position: SELECT substring('Guru99' from 1 for 4) 4 characters were extracted to return the above. We did not specify the starting position, so the extraction of the substring start at position 1. In this example, we want to extract the first 4 characters from the word Guru99: SELECT substring('Guru99' for 4) If you omit this parameter, the function will extract from starting_position to the end of the string. It denotes the number of characters to be extracted from the string. If you omit this parameter, the extraction will start from position 1, which is the first character in the string. It denotes the place where the extraction of the string will begin. The source string whose data type is varchar, char, string, etc. The PostgreSQL substring function takes the following syntax: substring( string )

Matching Substrings with SQL Regular Expression.

In this PostgreSQL tutorial, you will learn:

Instead of returning the whole string, it only returns a part of it.

The PostgreSQL substring function helps you to extract and return part of a string.

Postgresql regex