Weekly update in TiDB

Last week, we landed 41 PRs in the TiDB repository.

Added

• Introduce columnBufferAllocator for the vectorized evaluation
• Add the reserve methods to Column for the var-length types
• Make baseBuiltinFunc support the conversion from row-based evaluation to vectorized evaluation
• Add the support of follower read to TiDB

Improved

• Add the Times interface for chunk.Column
• Add the new rowcodec library

Fixed

• Increase the default concurrency factor of cost computing
• Rewrite in as eq when the rhs list has only one item
• Fix the incorrect behavior of index join
• Change the select ... for update statement to the normal select ... statement in the auto-commit case
• Fix the automatic retry when a transaction has the select for update statement
• Fix the panic when fetching date from the processlist table in some cases

Weekly update in TiSpark

Last week, we landed 24 PRs in the TiSpark repository and released TiSpark 2.1.3.

Fixed

• Prohibit the Aggregation or GroupBy pushdown in the case of double read
• Fix the error of Spark version reflection for the HDP release

Weekly update in TiKV and PD

Last week, we landed 31 PRs in the TiKV and PD repositories.

Added

• Support the validating parameters in rpn_expr/test_util.rs
• Set the not_found field to true in Getresponse when a key does not exist
• Exclude the shared block cache from the core dump

Improved

• Refine Ress and handle all Ress via EvalContext
• Replace std's HashMap to tikv_util's HashMap
• Migrate json_unquote to the RPN function

Fixed

• Fix the deadlock problem in Raft clusters
• Fix the duplicate ctx in the Readindex request
• Fix the bugs of float_str_to_int_str and refactor the implementation to the same as TiDB

New contributors (Thanks!)

tidb：

• francis0407
• lance6716

tikv：

• ethan-daocloud
• you06
• wujy-cs

parser:

• lauhg
• doggeral
• tangwz
• ichn-hu
• qiukun
• huaouo