What function is used to represent a certain character in Oracle?

Function that contains a certain character in Oracle

In Oracle, you can use the INSTR function to determine whether a string contains a certain character.

Syntax

<code>INSTR(string, search_string, start_position, occurrence)</code>

Parameters

• string: The string to search for.
• search_string: The character or substring to be found.
• start_position (optional): From which position in the string to start searching (counting from 1).
• occurrence (optional): The number of occurrences to find (counting from 1).

Return value

If search_string is found, return its first occurrence in string index position. If not found, returns 0.

Example

Find whether the character "r" exists in the string "Oracle":

<code>SELECT INSTR('Oracle', 'r');</code>

Result:

<code>3</code>

This Indicates that the character "r" is at position 3 (counting from 1) in the string "Oracle".

Find the third occurrence of the character "d" in the string "Database":

<code>SELECT INSTR('Database', 'd', 1, 3);</code>

Result:

<code>7</code>

This means that the character "d" appears in the string "Database" The third occurrence of " is in position 7 (counting from 1).

Note

• start_position parameter can only be used when the second parameter is a substring.
• occurrence Parameters can only be used when the first parameter is a string.
• If start_position or occurrence is negative or zero, treat it as 1.

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