text: -- Licensed to the Apache Software Foundation (ASF) under one
  -- or more contributor license agreements.  See the NOTICE file
  -- distributed with this work for additional information
  -- regarding copyright ownership.  The ASF licenses this file
  -- to you under the Apache License, Version 2.0 (the
  -- "License"); you may not use this file except in compliance
  -- with the License.  You may obtain a copy of the License at
  --
  --   http://www.apache.org/licenses/LICENSE-2.0
  --
  -- Unless required by applicable law or agreed to in writing,
  -- software distributed under the License is distributed on an
  -- "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  -- KIND, either express or implied.  See the License for the
  -- specific language governing permissions and limitations
  -- under the License.
  
  CREATE TYPE frequent_strings_sketch;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_in(cstring) RETURNS frequent_strings_sketch
       AS '$libdir/datasketches', 'pg_sketch_in'
       LANGUAGE C STRICT IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_out(frequent_strings_sketch) RETURNS cstring
       AS '$libdir/datasketches', 'pg_sketch_out'
       LANGUAGE C STRICT IMMUTABLE;
  
  CREATE TYPE frequent_strings_sketch (
      INPUT = frequent_strings_sketch_in,
      OUTPUT = frequent_strings_sketch_out,
      STORAGE = EXTERNAL
  );
  
  CREATE CAST (bytea as frequent_strings_sketch) WITHOUT FUNCTION AS ASSIGNMENT;
  CREATE CAST (frequent_strings_sketch as bytea) WITHOUT FUNCTION AS ASSIGNMENT;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_add_item(internal, int, varchar) RETURNS internal
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_add_item'
      LANGUAGE C IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_add_item(internal, int, varchar, bigint) RETURNS internal
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_add_item'
      LANGUAGE C IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_merge(internal, int, frequent_strings_sketch) RETURNS internal
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_merge'
      LANGUAGE C IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_from_internal(internal) RETURNS frequent_strings_sketch
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_from_internal'
      LANGUAGE C STRICT IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_to_string(frequent_strings_sketch) RETURNS TEXT
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_to_string'
      LANGUAGE C STRICT IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_to_string(frequent_strings_sketch, boolean) RETURNS TEXT
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_to_string'
      LANGUAGE C STRICT IMMUTABLE;
  
  CREATE AGGREGATE frequent_strings_sketch_build(int, varchar) (
      sfunc = frequent_strings_sketch_add_item,
      stype = internal,
      finalfunc = frequent_strings_sketch_from_internal
  );
  
  CREATE AGGREGATE frequent_strings_sketch_build(int, varchar, bigint) (
      sfunc = frequent_strings_sketch_add_item,
      stype = internal,
      finalfunc = frequent_strings_sketch_from_internal
  );
  
  CREATE AGGREGATE frequent_strings_sketch_merge(int, frequent_strings_sketch) (
      sfunc = frequent_strings_sketch_merge,
      stype = internal,
      finalfunc = frequent_strings_sketch_from_internal
  );
  
  CREATE TYPE frequent_strings_sketch_row AS (str varchar, estimate bigint, lower_bound bigint, upper_bound bigint);
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_result_no_false_positives(frequent_strings_sketch)
      RETURNS setof frequent_strings_sketch_row
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_result_no_false_positives'
      LANGUAGE C STRICT IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_result_no_false_positives(frequent_strings_sketch, bigint)
      RETURNS setof frequent_strings_sketch_row
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_result_no_false_positives'
      LANGUAGE C STRICT IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_result_no_false_negatives(frequent_strings_sketch)
      RETURNS setof frequent_strings_sketch_row
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_result_no_false_negatives'
      LANGUAGE C STRICT IMMUTABLE;
  
  CREATE OR REPLACE FUNCTION frequent_strings_sketch_result_no_false_negatives(frequent_strings_sketch, bigint)
      RETURNS setof frequent_strings_sketch_row
      AS '$libdir/datasketches', 'pg_frequent_strings_sketch_result_no_false_negatives'
      LANGUAGE C STRICT IMMUTABLE;
  
  