Name

get_keyword — Find a value in keyword vector

Synopsis

get_keyword ( keyword any ,
  searched_array vector ,
  default any ,
  no_copy integer );
 

Description

get_keyword performs a case sensitive seek for the occurrence of keyword from each even position of searched_array . If found,this returns the element following the occurrence of the keyword. If the keyword is not found this returns the default argument or NULL if the default is not supplied.

Parameters

keyword

String key value to be searched in the searched_array at even positions.

searched_array

An array of even length to be searched. Each even position is a string to search. Each odd position can be any value that may then be returned.

default

Any data to be returned if keyword is not matched in the searched_array.

no_copy

By default no_copy is false (0). If passed as true (non-zero integer) then the element to return is the original content of the array and the place in the array from which the element came gets set to 0.

This must in some cases be true, for example when the data being retrieved is not copyable, as in the case of a string output. While the default behavior is to return a copy of the element get_keyword will return the element itself and then set the place from which the element was retrieved to 0 if this argument is true.

Errors

Parameter data type checking errors

Table 24.37. Errors signalled by openxml

SQL Code Error Message Virtuoso Code
22023 get_keyword expects a vector of even length, not of length <n> SR057

Return Values

get_keyword returns the matched data if it is found. Otherwise it returns the default . When no default is defined, NULL is returned.

Examples

Example 24.133. Sample calls

get_keyword(2,vector(1,'primero',2,'segundo',
        3,'tercero'),NULL)              -> segundo
get_keyword('tercero',vector('primero',1,'segundo',
        2,'tercero',3), 'NOT FOUND!'))  -> 3

x := vector ('a', 2);
y := get_keyword ('a', x, -1, 1);
The first call returns 2
y := get_keyword ('a', x, -1, 1);
the second call returns 0 as the data was set to 0 by the previous call.