sql> create table pdba (id, time) partition by range (time)2 (partition p1 values less than (to_date('2010-10-1', 'yyyy-mm-dd')),3 partition p2 values less than (to_date('2010-11-1', 'yyyy-mm-dd')),4 partition p3 values less than (to_date('2010-12-1', 'yyyy-mm-dd'...
数据库集群的逻辑结构 PostgreSQL天然集群,多个集群可以组成集簇,有点类似军队的连、团、旅这样的组织规则。对于我们日常学习使用的单节点则是单个集簇单个集群,自己就是集群。 PostgreSQL如何管理这种集群规则?答案是通过一个无符号4个字节的标识进行管理,一个对象就是集群里的一个数据库。 1.2 数据库对象和对象符号...
NodeTag type;/* result relation's range table index, or 0 if not in range table *///RTE索引Index ri_RangeTableIndex;/* relation descriptor for result relation *///结果/目标relation的描述符Relation ri_RelationDesc;/* # of indices existing on result relation *///目标关系中索引数目intri_N...
IF v_partition_keyISNOTNULLTHENv_table_ddl :=v_table_ddl||' PARTITION BY '||v_partition_key;ENDIF;ENDIF; v_table_ddl :=v_table_ddl||';'||E'\n';-- suffix create statement with all of the indexes on the tableFORv_index_recordINSELECTregexp_replace(indexdef,' "?'||schemaname|...
create table db_test(id int primary key, name varchar(50), age int); postgres=# select * from pg_class where relname ='db_test'; oid | relname | relnamespace | reltype | reloftype | relowner | relam | relfilenode | reltablespace | relpages | reltuples | relallvisible | reltoa...
#default_statistics_target = 100 # 为没有通过ALTER TABLE SET STATISTICS设置列相关目标的表列设置默认统计目标。 range 1-10000 # 默认值是 100 #constraint_exclusion = partition # constraint_exclusion的允许值是on(对所有表检查约束)、off(从不检查约束)和partition(只对继承的子表和UNION ALL子查询检查约...
The partitioned table is itself empty. A data rowinsertedinto the table is routed to a partitionbasedon the value of columnsorexpressions in the partition key. If no existing partition matches the values in the new row, an error willbereported. ...
3)Maintenance_work_mem:用于限制vacuum、create index、reindex、alter table add foreign key所使用的最大内存量。 由于每个session只能执行这些操作中的一个,而且PG也会限制这些操作同时执行,所以Maintenance_work_mem可以比work_mem设置的更大一些。 注:当autovacuum运行时,可能会分配多达autovacuum_max_workers次的内...
Create a check constraint on the existing table Define a check constraint that matches the partition boundaries as that of the old table when it’s attached as a partition to the new table. The check constraint must be defined on the column that has been u...
"partition": "abc_0" } 11. 非堵塞式创建分区表,以及后台自动将主表数据迁移到分区表,非堵塞式。 Non-blocking concurrent table partitioning; 12. 支持FDW,通过配置参数pg_pathman.insert_into_fdw=(disabled | postgres | any_fdw)支持postgres_fdw或任意fdw ...