Release Notes for v2.0-alpha.20171218

December 18, 2017

SQL Language Changes

  • Added support for read-only transactions via PostgreSQL-compatible syntax. #20547
    • SET SESSION CHARACTERISTICS AS TRANSACTION READ ONLY/READ WRITE
    • SET TRANSACTION READ ONLY/READ WRITE
    • SET default_transaction_read_only
    • SET transaction_read_only
  • For compatibility with PostgreSQL, the return type of the date_trunc(STRING,TIME) function was changed from TIME to INTERVAL, and the return type of the date_trunc(STRING,DATE) function was changed from DATE to TIMESTAMPTZ. #20467

Bug Fixes

  • Fixed a bug preventing CockroachDB from starting when the filesystem generates a lost+found directory in the Cockroach data directory. #20565
  • Fixed the over-counting of memory usage by aggregations. #20585
  • Fix a panic when using the date_trunc(STRING,TIMESTAMP) or date_trunc(STRING,DATE) function during queries that run with the distributed execution engine. #20467
  • Fixed a bug where the date_trunc(STRING,TIMESTAMP) function would return a TIMESTAMPTZ value. #20467
  • Fixed a race condition that would result in some queries hanging after cancellation. #20088
  • Fixed a bug allowing privileges to be granted to non-existent users. #20438

Performance Improvements

  • Queries that use inequalities using tuples (e.g., (a,b,c) < (x,y,z)) are now slightly better optimized. #20484
  • IS DISTINCT FROM and IS NOT DISTINCT FROM clauses are now smarter about using available indexes. #20346

Doc Updates