ts_tumble.sqlx

config { hasOutput: true }
/*
 * Copyright 2020 Google LLC
 *
 * Licensed 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.
 */

-- ts_tumble:
-- Input:
-- input_ts: timestamp to be divided into a [tumble window](https://cloud.google.com/dataflow/docs/reference/sql/streaming-extensions#tumble)
-- tumble_seconds: size of the tumble window in seconds
-- Output: the starting TIMESTAMP of the tumble winow the input_ts belongs to
CREATE OR REPLACE FUNCTION ${self()}(input_ts TIMESTAMP, tumble_seconds INT64)
RETURNS TIMESTAMP
AS (
  IF (
    tumble_seconds > 0, 
    TIMESTAMP_SECONDS(DIV(UNIX_SECONDS(input_ts), tumble_seconds) * tumble_seconds), 
    NULL
  )
);