[FLINK-32815] Add HASHCODE support in Table API

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Implemented
• Fix Version/s: 1.19.0
• Labels: pull-request-available stale-major
• Assignee: Hanyu Zheng
• Reporter: Hanyu Zheng
• Created: 08/Aug/23 19:11
• Updated: 23/Feb/24 13:04
• Resolved: 15/Jan/24 11:48

Description

This is an implementation of HASHCODE internal function

The hashcode function generates a hash code for a given input value, including support for computing hash values of binary data types. It creates a unique integer that represents the value passed to the function.

Brief change log

• HASHCODE for Table API 

Syntax:

HASHCODE(value)

Arguments:

• value: the value to be hashed.

Returns: The function returns a unique integer representing the hash code of the value. If the input argument is NULL, the function returns NULL.

Because it is an internal function, so it will not support sql anymore.

see also:

Java: https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#hashCode--

Python: https://docs.python.org/3/library/functions.html#hash

C#: https://docs.microsoft.com/en-us/dotnet/api/system.object.gethashcode

SQL Server: https://docs.microsoft.com/en-us/sql/t-sql/functions/checksum-transact-sql

MySQL: https://dev.mysql.com/doc/refman/8.0/en/encryption-functions.html#function_md5

PostgreSQL: https://www.postgresql.org/docs/current/pgcrypto-hash.html

Oracle: https://docs.oracle.com/en/database/oracle/oracle-database/19/sqlrf/ORA-HASH.html

Google Cloud BigQuery: https://cloud.google.com/bigquery/docs/reference/standard-sql/functions-and-operators#farm_fingerprint

AWS Redshift: https://docs.aws.amazon.com/redshift/latest/dg/MD5.html

Issue Links

• links to: GitHub Pull Request #23118
• links to: GitHub Pull Request #24070