Deleting a Specified Character

trim([leading |trailing |both] [characters] from string)

Description: Deletes specific characters from the beginning, end, or both ends of a string.

Parameters:

• leading: deletes spaces or specified characters at the beginning of a string.
• trailing: deletes spaces or specified characters at the end of a string.
• both: deletes spaces or specified characters at the beginning and end of a string (default behavior).
• characters: (optional) specifies specific characters to be deleted. If this parameter is not specified, spaces are deleted by default.
• string: original string to be processed.

Return type: varchar

Examples:

Delete the characters x at the beginning and end of the string xTomxx.

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SELECT trim(BOTH 'x' FROM 'xTomxx');
 btrim
-------
 Tom
(1 row)

SELECT trim('x' FROM 'xTomxx');
 btrim
-------
 Tom
(1 row)

Delete the character x at the beginning of the string xTomxx.

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SELECT trim(LEADING 'x' FROM 'xTomxx');
 ltrim
-------
 Tomxx
(1 row)

Delete the character x at the end of the string xTomxx.

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SELECT trim(TRAILING 'x' FROM 'xTomxx');
 rtrim
-------
 xTom
(1 row)

rtrim(string [, characters])

Description: Deletes the specified characters from the end of a string.

Parameters:

• string: original string to be processed.
• characters (optional): specifies the set of characters to be deleted from the end of a string. By default, all blank characters (for example, spaces) are deleted.

Return type: varchar

Example:

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SELECT rtrim('DataxBasexx','x');
   rtrim
-----------
 DataxBase
(1 row)

SELECT rtrim('   Data  ');
  rtrim
---------
    Data
(1 row)

ltrim(string [, characters])

Description: Deletes the specified strings from the beginning of a string.

Parameters:

• string: original string to be processed.
• characters (optional): specifies the set of characters to be deleted from the beginning of a string. By default, all blank characters (for example, spaces) are deleted.

Return type: varchar

Example:

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SELECT ltrim('xxDataxBase','x');
   ltrim
-----------
 DataxBase
(1 row)

SELECT ltrim('   Data  ');
 ltrim
--------
 Data
(1 row)