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Deprecated version

This document refers to a deprecated version of the RQL programming language.

Please go here for documentation related to the latest supported version.

Merges a collection of strings into a single string, with a separator. Null strings are skipped. Null collections lead to a null result. MKSTRING can be applied any expression, for example a SELECT statement evaluating to a collection of strings.

MKSTRING(<collection of strings>, <separator string>)
MKSTRING(["string1", "string2"], " - ") // "string1 - string2"
MKSTRING(["string1"], " - ") // "string1"
MKSTRING(["12", null, "34"], ";") // "12;34"
MKSTRING(countries UNION ALL cities, ";")
MKSTRING((SELECT name FROM people), ";")

Keep in mind the possibility of a parser ambiguity when passing a complex expression as a parameter to MKSTRING: in the example above parenthesis are required.