用例样表
CREATE TABLE "pt" (
"i" int(11) DEFAULT NULL,
"j" int(11) DEFAULT NULL
) ENGINE=EXPRESS DEFAULT CHARSET=utf8
TABLESPACE='sys_tablespace'
PARTITION BY LIST (mod(i,2))
(PARTITION p0 VALUES IN (0) TABLESPACE = 'sys_tablespace' ENGINE =
EXPRESS,
PARTITION p1 VALUES IN (1) TABLESPACE = 'sys_tablespace' ENGINE =
EXPRESS)
语法DELETE
DELETE ... FROM [vc_name.][database_name.]
(partition_name1[, partition_name2, ...])]
示例:
gbase> insert into pt values(1,1),(2,2);
Query OK, 2 rows affected (Elapsed: 00:00:01.70)
gbase> delete from pt partition(p1);
Query OK, 1 row affected (Elapsed: 00:00:03.27)
gbase> delete from pt partition(p0,p1);
Query OK, 1 row affected (Elapsed: 00:00:00.11)
语法UPDATE
UPDATE [vc_name.][database_name.]
GBase 8a MPP Cluster 产品手册
5 数据库管理指南
文档版本953(2022-09-15)
南大通用数据技术股份有限公司
1065
(partition_name1[, partition_name2, ...])] set…
说明:分区条件列不允许更新
示例:
gbase> insert into pt values(1,1),(2,2);
Query OK, 2 rows affected (Elapsed: 00:00:01.00)
更新指定分区数据
gbase> update pt partition (p0) set j=j+1;
Query OK, 1 row affected (Elapsed: 00:00:02.41)
gbase> select * from pt;
+------+------+
| i
| j
|
+------+------+
|
2 |
3 |
|
1 |
1 |
+------+------+
2
rows in set (Elapsed: 00:00:01.20)
gbase> update pt partition (p0,p1) set j=j+1;
Query OK, 2 rows affected (Elapsed: 00:00:03.09)
Rows matched: 2
Changed: 2
Warnings: 0
gbase> select * from pt;
+------+------+
| i
| j
|
+------+------+
|
2 |
4 |
|
1 |
2 |
+------+------+
3
rows in set (Elapsed: 00:00:00.47)
GBase 8a MPP Cluster 产品手册
5 数据库管理指南
文档版本953(2022-09-15)
南大通用数据技术股份有限公司
1066
快速更新模式下更新指定分区的数据
gbase> set gbase_fast_update=1;
Query OK, 0 rows affected (Elapsed: 00:00:01.39)
gbase> update pt partition (p0) set j=j+1;
Query OK, 1 row affected (Elapsed: 00:00:14.89)