INSTR function returns the starting position of a substring within a string.

Syntax:

INSTR(string, substring [, position [, occurrence]]) 

Notes:

• position specifies the staring position for search, the default is 1 (the beginning of string)
• If position is negative INSTR counts and searches backward from the end of string
• occurrence specifies which occurrence of substring to search, the default is 1 (finds the first occurrence)
• If string is NULL the return value is NULL
• if string is not NULL and substring not found the return value is 0

Return Type:

INT

Example 1:

Find the first occurrence starting from the beginning:

INSTR('abc', 'b')                      -- Result 2

Example 2:

Find the first occurrence starting from the 3rd position:

INSTR('abcabc', 'b', 3)                -- Result 5

Example 3:

Find the second occurrence starting from the 3rd position:

INSTR('abcabcabc', 'b', 3, 2)          -- Result 8

Example 4:

Find the first occurrence starting from the 3rd position from the end:

INSTR('abcabcabc', 'b', -3)            -- Result 5

Example 5:

Find the second occurrence starting from the 3rd position from the end:

INSTR('abcabcabc', 'b', -3, 2)         -- Result 2

Compatibility: Oracle, IBM DB2 and Teradata.

Version: PL/HQL 0.3.11