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zettadb / kunlun

KunlunBase is a distributed relational database management system(RDBMS) with complete NewSQL capabilities and robust transaction ACID guarantees and is compatible with standard SQL. Applications which used PostgreSQL or MySQL can work with KunlunBase as-is without any code change or rebuild because KunlunBase supports both PostgreSQL and MySQL connection protocols and DML SQL grammars. MySQL DBAs can quickly work on a KunlunBase cluster because we use MySQL as storage nodes of KunlunBase. KunlunBase can elastically scale out as needed, and guarantees transaction ACID under error conditions, and KunlunBase fully passes TPC-C, TPC-H and TPC-DS test suites, so it not only support OLTP workloads but also OLAP workloads. Application developers can use KunlunBase to build IT systems that handles terabytes of data, without any effort on their part to implement data sharding, distributed transaction processing, distributed query processing, crash safety, high availability, strong consistency, horizontal scalability. All these powerful features are provided by KunlunBase. KunlunBase supports powerful and user friendly cluster management, monitor and provision features, can be readily used as DBaaS.
http://www.kunlunbase.com
Apache License 2.0
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修正索引的null first属性，使得优化器能够正确判断和使用索引 #777

Open jd-zhang opened 2 years ago

jd-zhang commented 2 years ago

Issue migrated from trac ticket # 842 www.kunlunbase.com

component: computing nodes | priority: major

2022-06-21 14:05:31: smith created the issue

abc=# drop index t2_a_idx2; create index on t2(a);
DROP INDEX
CREATE INDEX
abc=# \d+ t2;
                                    Table "public.t2"
 Column |  Type   | Collation | Nullable | Default | Storage | Stats target | Description
--------+---------+-----------+----------+---------+---------+--------------+-------------
 a      | integer |           |          |         | plain   |              |
Indexes:
    "t2_a_idx2" btree (a NULLS FIRST)
Options: shard=1

abc=#