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LIKE Predicate (like_predicate) Locate the document in its SAP Library structure

A LIKE predicate (like_predicate) is a predicate that is used to search for character strings that have a certain pattern. This pattern can be a certain character string or any sequence of characters (whose length may or may not be known).

Syntax

<like_predicate> ::= <expression> [NOT] LIKE <like_expression> [ESCAPE <expression>]

<like_expression> ::= <expression> | '<pattern_element>...'
<pattern element> ::= <match string> | <match set>

<match_string> ::= % | X'1F'
<match_set> ::= <underscore> | X'1E' | <match_char>

<underscore> ::= _ (underscore)
<match_char>    ::=
every character other than %, X'1F', _ (underscore), X'1E'

Explanation

x NOT LIKE y has the same result as NOT(x LIKE y).

 

Result of x LIKE y

x or y are NULL values

x LIKE y is undefined

x and y are non-NULL values

x LIKE y is either true or false

x can be split into substrings with the result that:

A substring of x is a sequence of 0, 1, or more contiguous characters, and each character of x belongs to exactly one substring.

The number of substrings of x and y is identical.

If the nth pattern element (pattern_element) of y is a sequence of characters and the nth substring of x is a sequence of 0 or more characters.

x LIKE y is true

<expression>

The expression (expression) in the LIKE expression (like_expression) must supply an alphanumeric value or a date or time value.

<pattern_element>

If a match_string is specified, this position in the search pattern can be replaced by any number of characters.

If a match_set is specified, this position in the search pattern can be replaced by the exact number of characters specified in the match_set.

If an underscore or X'1E' is used, this position in the pattern can be replaced by any one character.

If match_char is used, this position in the pattern can be replaced by the specified character itself.

ESCAPE

An escape character (ESCAPE <expression>) must be used if you want to search for an <underscore>, '%', or the hexadecimal value X'1E' or X'1F' in the LIKE predicate.

If ESCAPE <expression> is specified, the corresponding expression (expression) must supply an alphanumeric value that consists of just one character. If this escape character is contained in the LIKE expression (like_expression), the following character must be one of the special characters <underscore>, %, X’1E’, or X’1F’. This special character is then viewed as standing for itself.

Example

Search for any character string with a minimum length of 1: LIKE '%_'
Search for a character string in which a fixed number of characters is known: LIKE'_c_'
Search for a character string with any number of characters, whereby the character string must contain an underscore: LIKE '%:_%'ESCAPE':'

Example

SELECT name, zip FROM customer
  WHERE name LIKE '%ft'

Customers whose name ends with 'ft':

NAME

ZIP

Datasoft

90018

 

SELECT name, firstname FROM customer
  WHERE name LIKE 'P_____'

Finding all customers whose names consist of six letters and begin with 'P'

NAME

FIRSTNAME

Porter

Jenny

Peters

Joseph

 

SELECT name, firstname FROM customer
  WHERE name LIKE '_%p%'

Customers with a 'p' in their name from the second position

NAME

FIRSTNAME

Randolph

Martin

 

 

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