op:json-null() as map:map
This function constructs a JSON null node.
xquery version "1.0-ml"; import module namespace op="http://marklogic.com/optic" at "/MarkLogic/optic.xqy"; op:from-literals(( map:entry("row",1)=>map:with("gp",1)=>map:with("nm","alpha")=> map:with("str","a")=>map:with("num",10)=>map:with("bool", true() ), map:entry("row",2)=>map:with("gp",1)=>map:with("nm","beta" )=> map:with("str","b")=>map:with("num",20)=>map:with("bool", false() ), map:entry("row",3)=>map:with("gp",2)=>map:with("nm","gamma")=> map:with("str","c")=>map:with("num",30)=>map:with("bool", true() ), map:entry("row",4)=>map:with("gp",2)=>map:with("nm","delta")=> map:with("str","d")=>map:with("num",40)=>map:with("bool", false() ) )) => op:where(op:eq(op:col("gp"), 1)) => op:select(("row", op:as("node", op:json-array(( op:json-string(op:col("str")), op:json-number(op:col("num")), op:json-boolean(op:col("bool")), op:json-null() ))) )) => op:order-by("row") => op:result()