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LPAD()

Available in: DSQL, PSQL

Added in: 2.1

Description: Left-pads a string with spaces or with a user-supplied string until a given length is reached.

Result type: VARCHAR(32765) or BLOB

Syntax: 

LPAD (str, endlen [, padstr])
  • This function fully supports text BLOBs of any length and character set.

  • If str is a BLOB, the result is a BLOB. Otherwise, the result is a VARCHAR(32765).

  • If padstr is given and equals '' (empty string), no padding takes place.

  • If endlen is less than the current string length, the string is truncated to endlen, even if padstr is the empty string.

Important

If the external function LPAD is declared in your database, it will override the internal function. To make the internal function available, DROP or ALTER the external function (UDF).

Tip

With (VAR)CHARs, it is generally wise to CAST the result to a smaller size. The default result length of 32765 may, in combination with other output columns, lead to a “block size exceeds implementation restriction” error.

Examples: 

lpad ('Hello', 12)                 -- returns '       Hello'
lpad ('Hello', 12, '-')            -- returns '-------Hello'
lpad ('Hello', 12, '')             -- returns 'Hello'
lpad ('Hello', 12, 'abc')          -- returns 'abcabcaHello'
lpad ('Hello', 12, 'abcdefghij')   -- returns 'abcdefgHello'
lpad ('Hello', 2)                  -- returns 'He'
lpad ('Hello', 2, '-')             -- returns 'He'
lpad ('Hello', 2, '')              -- returns 'He'

Warning

When used on a BLOB, this function may need to load the entire object into memory. Although it does try to limit memory consumption, this may affect performance if huge BLOBs are involved.

See also: RPAD()

Prev: LOWER()Firebird Documentation IndexUp: Internal functionsNext: MAXVALUE()
Firebird Documentation IndexFirebird 2.1 Language Ref. UpdateInternal functions → LPAD()