UNIX_TIMESTAMP
Converts a SQL timestamp to a Unix timestamp that is expressed in milliseconds since '1970-01-01 00:00:00' UTC and that is a BIGINT.
Syntax
UNIX_TIMESTAMP(timeStampExpr)
Parameters
timeStampExpr
A SQL TIMESTAMP value.
Example
Example Dataset
The examples following are based on the sample stock dataset that is part of Getting Started Exercise in the Amazon Kinesis Analytics Developer Guide.
Note
The sample dataset has been modified to include a Timestamp value (CHANGE_TIME).
To run each example, you need an Amazon Kinesis Analytics application that has the input stream for the sample stock ticker. To learn how to create an Analytics application and configure the input stream for the sample stock ticker, see Getting Started Exercise in the Amazon Kinesis Analytics Developer Guide.
The sample stock dataset has the schema following.
(ticker_symbol VARCHAR(4), sector VARCHAR(16), change REAL, change_time TIMESTAMP, --The timestamp value to convert price REAL)
Example 1: Convert a Timestamp to a UNIX Timestamp
In this example, the change_time
value in the source stream is converted to a TIMESTAMP value in the in-application stream.
CREATE OR REPLACE STREAM "DESTINATION_SQL_STREAM" ( ticker_symbol VARCHAR(4), SECTOR VARCHAR(16), CHANGE REAL, CHANGE_TIME BIGINT, PRICE REAL); CREATE OR REPLACE PUMP "STREAM_PUMP" AS INSERT INTO "DESTINATION_SQL_STREAM" SELECT STREAM TICKER_SYMBOL, SECTOR, CHANGE, UNIX_TIMESTAMP(CHANGE_TIME), PRICE FROM "SOURCE_SQL_STREAM_001"
The preceding example outputs a stream similar to the following.
Notes
UNIX_TIMESTAMP is not part of the SQL:2008 standard. It is an Amazon Kinesis Data Analytics streaming SQL extension.