PL/SQL Trim Function

Introduction

The Trim function in PL/SQL is used to remove the leading or trailing spaces or characters from a given string. It is a commonly used function in PL/SQL programming to clean up data, especially when dealing with user input.

Syntax

The syntax for the Trim function in PL/SQL is as follows:

TRIM([LEADING | TRAILING | BOTH] [characters] FROM string)

• LEADING: Removes the specified characters only from the beginning of the string.
• TRAILING: Removes the specified characters only from the end of the string.
• BOTH: Removes the specified characters from both the beginning and end of the string.
• characters: Specifies the characters to be removed from the string. It is an optional parameter. If it is not specified, the function will remove all whitespace characters.

Examples

Here are some examples that demonstrate how the Trim function works in PL/SQL:

Example 1: Trim leading and trailing spaces

DECLARE
   str1 VARCHAR2(20) := '  hello, world  ';
   str2 VARCHAR2(20);
BEGIN
   str2 := TRIM(str1);
   DBMS_OUTPUT.PUT_LINE(str2); -- Output: 'hello, world'
END;

This example demonstrates how to use the Trim function to remove leading and trailing spaces from a string. The TRIM function is applied to the string str1, and the resulting string is stored in str2.

Example 2: Trim specific characters

DECLARE
   str1 VARCHAR2(20) := 'TTThello, worldTTT';
   str2 VARCHAR2(20);
BEGIN
   str2 := TRIM('T' FROM str1);
   DBMS_OUTPUT.PUT_LINE(str2); -- Output: 'hello, world'
END;

This example demonstrates how to use the Trim function to remove a specific character from a string. The TRIM function is applied to the string str1, and the character 'T' is specified as the character to be removed. The resulting string is stored in str2.

Conclusion

The Trim function is a powerful tool that can be used to clean up data in PL/SQL programming. By removing unnecessary spaces or characters from a given string, you can improve the quality and accuracy of your data. If you're unfamiliar with the Trim function, take some time to experiment with it and incorporate it into your PL/SQL programming arsenal.