Introduction to the use of SUBSTR functions in Oracle

In Oracle/plsql, the SUBSTR functions allows you to extract a substring a string. The syntax for the SUBSTR function is:

substr (String, start_position, [length])

Description

The string is the source string.

Start_position is the position for extraction. The the position in the ' string is always 1.

The length is optional. It is the number of characters to extract. Ifthis parameter is omitted, substr'll return the entire string.

For example:

SUBSTR (' This are a test ', 6, 2) would return ' is '

SUBSTR (' This are a test ', 6) would return ' is a test '

substr (' Techonthenet ', 1, 4) would return ' Tech '

substr (' techonthenet ', -3, 3) would return ' Net '

substr (' Techonthenet ',-6, 3) would return ' the '

substr (' techonthenet ',-8, 2) would return ' on '

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