Weekly update in TiDB

Last two weeks, we landed 25 PRs in the TiDB repositories.

Added

• Support basic privilege framework: #2423, #2557, #2603, #2607,

• Support ALTER [COLUMN] col_name SET DEFAULT statement.

• Validate column default value when creating table.

• Support ALTER TABLE ... DROP DEFAULT statement.

• Support changing default value and comment in alter table statement.

Fixed

• Fix build on i386.

• Fix output format of prometheus interval log.

• Clean up log: #2599, #2601

• Fix a bug in HashJoin executor: some errors are ignored.

• Fix a bug in arithmetic expression type inference.

• Fix a bug in builtin function timediff.

Improved

• Speed up unit tests.

• Make test cases more stable: #2595, #2596

• Remove useless code in parser package.

• Change string default collation to utf8_bin. We do not support case insensitive comparation yet.

Weekly update in TiKV

Last week, We landed 14 PRs in the TiKV repositories.

Added

• Use seek_for_prev directly.

• Refactor cut_row and cut_idx_key for row value analysis in coprocessor.

• Extract an interface to support different snapshot format.

Fixed

• Fix panic when stop scheduler worker.

• Fix invalid link in PD readme.

Improved

• Evaluate logic operations lazily.

• Use prefix seek to speed up read for Write CF.

• Separate advance to advance_ready and advance_apply for async-apply later.

• Use shutdown to do cleanup when stop worker.