Class MapContainsKey

java.lang.Object
dev.frostlake.functions.BuiltInFunction
dev.frostlake.functions.scalar.semistructured.MapContainsKey

public class MapContainsKey extends BuiltInFunction
MAP_CONTAINS_KEY(key, map) — whether the map holds the key. The MAP is the SECOND argument here, the one place in the family where it is not first. Live-verified: a missing key is FALSE, an empty map is FALSE, and a NULL on EITHER side is NULL rather than FALSE — MAP_CONTAINS_KEY(NULL, <{'a':1}>) and MAP_CONTAINS_KEY('a', NULL::MAP(VARCHAR,INT)) both answer NULL.
  • Constructor Details

    • MapContainsKey

      public MapContainsKey()
  • Method Details

    • evaluate

      public Object evaluate(List<Object> args)
      Description copied from class: BuiltInFunction
      Computes the function's result over its already-evaluated argument values. A SQL NULL argument arrives as Java null, and returning null makes the SQL result NULL.
      Specified by:
      evaluate in class BuiltInFunction
      Parameters:
      args - the argument values, in call order
      Returns:
      the function's value for these arguments, or null for SQL NULL
    • getMinArgCount

      public int getMinArgCount()
      Description copied from class: BuiltInFunction
      The fewest arguments a call to this function may pass; fewer is an argument-count error.
      Specified by:
      getMinArgCount in class BuiltInFunction
      Returns:
      the minimum accepted argument count
    • getMaxArgCount

      public int getMaxArgCount()
      Description copied from class: BuiltInFunction
      The most arguments a call to this function may pass; Integer.MAX_VALUE marks a variadic function (see BuiltInFunction.isVariadic()).
      Specified by:
      getMaxArgCount in class BuiltInFunction
      Returns:
      the maximum accepted argument count