Tsurugi 1.0.0 - Release Notes (en)

[akirakw]

1.0.0 Release Notes

Overview

We are happy to release Tsurugi 1.0.0, our first official release version.

This version includes many new SQL features, similar to the previous version, as well as experimental support for transaction log compression while the database is running and fixes for critical issues related to transaction logs.

New Features and Improvements

• SQL

  • Official support for the LIMIT clause
    • Removed the restriction that it could only be used in combination with the ORDER BY clause, and resolved some out-of-spec behaviors.
  • Support for Identity columns (GENERATED ... AS IDENTITY)
    • Allows the definition of Identity columns that automatically generate unique values.
    • Internally uses sequences to generate values.
  • Support for set operators
    • UNION ALL
    • UNION DISTINCT
    • EXCEPT DISTINCT
    • INTERSECT DISTINCT
  • Support for CASE expressions
    • Allows returning values based on conditions using CASE expressions.
  • Support for the NULLIF function
  • Support for the COALESCE function
  • Support for the DEFAULT VALUES clause in INSERT statements
  • Support for dumping BINARY and VARBINARY types via the dump API and the tgdump command
  • Partial support for index-based join processing (Index Join)
    • In this version, Index Join does not support some join operations. Therefore, for query execution plans that use unsupported join operations, the join processing will be changed to Shuffle Join.

• Transaction

  • (Experimental Support) Transaction log compression while the database is running
    • In addition to the existing transaction log compression feature during database shutdown provided by the tglogutil-compaction command, this version introduces the ability to compress transaction logs while the database is running.
    • This feature is experimental. The provided commands and features are subject to change upon official support. It is recommended to take a backup of the database before using this feature.
    • For details, refer to Tsurugi 1.0.0 - Known Issues(en) - TSURUGI-IS-289 Database startup becomes slower as the transaction log increases.

• Endpoint

  • Performance improvements for queries returning large amounts of data over TCP connections.

• CLI

  • Support for displaying help information for the tgctl command using tgctl --help.

For details on SQL features, refer to Available SQL features in Tsurugi.

Bug Fixes

• SQL

  • Fixed an issue where the presence of join conditions with different data types in JOIN clauses could cause abnormal termination.
  • Fixed an issue where casting CHAR and VARCHAR types to shorter lengths could leave invalid values at the end.
  • Fixed an issue where specifying a null value as an argument to the octet_length function could cause abnormal termination.
  • Fixed an issue where specifying a large number of elements in IN clause value lists or OR operators could cause abnormal termination.
  • Fixed an issue where executing SELECT COUNT(DISTINCT <column_name>) on CHAR/BINARY/VARCHAR/VARBINARY columns containing data longer than 16 bytes could result in incorrect results.
  • Fixed an issue where inefficient execution plans could be chosen for queries using OUTER JOIN under certain conditions.

• Transaction

  • Fixed an issue where executing DROP TABLE on a table with existing data could leave undeletable log information.
    • There are important notes regarding migration from older versions related to this issue. For details, refer to Tsurugi 1.0.0 - Known Issues(en) - TSURUGI-IS-923 When DROP TABLE statement removes tables with any records, then the records will remain in the transaction logs with inconsistent state.

• Endpoint

  • Fixed an issue where queries via tsurugi_fdw would incorrectly timeout and cause tsurugi_fdw to terminate abnormally after 5 seconds.

Known Issues

For known issues in this version and supplementary information on issues fixed in this version, refer to the following link.

• Tsurugi 1.0.0 - Known Issues(en)

Others

For a list of changes in this version, refer to the following Changelog.

• Tsurugi 1.0.0 - Changelog

For upgrade instructions from previous versions, refer to the following document.

• Tsurugi Upgrade Guide