title | aliases | ||
---|---|---|---|
TiDB 2.1 RC4 Release Notes |
|
On October 23, 2018, TiDB 2.1 RC4 is released. Compared with TiDB 2.1 RC3, this release has great improvement in stability, SQL optimizer, statistics information, and execution engine.
- SQL Optimizer
- SQL Execution Engine
- Fix the precision issue of the
AVG
function #7874 - Support using the
EXPLAIN ANALYZE
statement to check the runtime statistics including the execution time and the number of returned rows of each operator during the query execution process #7925 - Fix the panic issue of the
PointGet
operator when a column of a table appears multiple times in the result set #7943 - Fix the panic issue caused by too large values in the
Limit
subclause #8002 - Fix the panic issue during the execution process of the
AddDate
/SubDate
statement in some cases #8009
- Fix the precision issue of the
- Statistics
- Fix the issue of judging the prefix of the histogram low-bound of the combined index as out of range #7856
- Fix the memory leak issue caused by statistics collecting #7873
- Fix the panic issue when the histogram is empty #7928
- Fix the issue that the histogram bound is out of range when the statistics is being uploaded #7944
- Limit the maximum length of values in the statistics sampling process #7982
- Server
- Refactor Latch to avoid misjudgment of transaction conflicts and improve the execution performance of concurrent transactions #7711
- Fix the panic issue caused by collecting slow queries in some cases #7874
- Fix the panic issue when
ESCAPED BY
is an empty string in theLOAD DATA
statement #8005 - Complete the “coprocessor error” log information #8006
- Compatibility
- Set the
Command
field of theSHOW PROCESSLIST
result toSleep
when the query is empty #7839
- Set the
- Expressions
- DDL
- Fix the issue that the tombstone TiKV is not removed from Grafana #1261
- Fix the data race issue when grpc-go configures the status #1265
- Fix the issue that the PD server gets stuck caused by etcd startup failure #1267
- Fix the issue that data race might occur during leader switching #1273
- Fix the issue that extra warning logs might be output when TiKV becomes tombstone #1280
- Optimize the RocksDB Write stall issue caused by applying snapshots #3606
- Add raftstore
tick
metrics #3657 - Upgrade RocksDB and fix the Write block issue and that the source file might be damaged by the Write operation when performing
IngestExternalFile
#3661 - Upgrade grpcio and fix the issue that “too many pings” is wrongly reported #3650