Multiple primary keys for table are not allowed The cause of error: There is already a primary key created. Check the primary key or drop the existing primary key. Create table and primary key CREATE TABLE test.products( product_id numeric, product_name varchar(500), category varchar(100)...
Postgres-XL的Datanode节点负责实际存取数据,数据在多个Datanode上的分布有两种方式:复制模式和分片模式,复制模式下,一个表的数据在指定的节点上存在多个副本;分片模式下,一个表的数据按照指定的规则分布在多个数据节点上,这些节点共同保存一份完整的数据。这两种模式的选择是在创建表的时候执行CREATE TABLE语句指定的,也...
The row of the table can be uniquely identified using a column or group of columns termed as a primary key. We can specify the primary keys using the primary key constraints. The PostgreSQL Primary Key constraint is the combination of a UNIQUE constraint and a NOT NULL constraint. The table...
PostgreSQL will create a primary key constraint as table_name_pkey that's employee_pkey for the employee table, as shown below.To define the primary key on multiple columns, it needs to be defined at the table level like below. Syntax: Multi-column Primary Key Copy CREATE TABLE [IF NOT ...
postgres=#createtableperf_test_ins(id serial8primarykey, info text, crt_timetimestamp); alCREATETABLEpostgres=#altersequence perf_test_ins_id_seq cache10000;ALTERSEQUENCE 创建测试脚本,不停插入 vi test.sqlinsertintoperf_test_ins(info,crt_time)values('test',now()); ...
CREATETABLEdevice_types ( device_type_idintprimarykey, device_type_nametextnotnullunique);-- replicate the table across all nodes to enable foreign keys and joins on any columnSELECTcreate_reference_table('device_types');-- insert a device typeINSERTINTOdevice_types (device_type_id, device_typ...
Supported SET IDENTITY_INSERT for three part relation references. Fixed an issue with the HASHBYTES function to ensure correct behavior when processing NVARCHAR argument. Fixed the issue of CREATE PARTITION SCHEME not supporting “PRIMARY” syntax. Fixed the issue of UPDATE/DELETE of table variable qu...
Use pglogical.wait_for_subscription_sync_complete to wait for completion. Parameters: subscription_name - name of the existing subscription truncate - if true, tables will be truncated before copy, default false pglogical.alter_subscription_resynchronize_table(subscription_name name, relation regclass) ...
Let’s not forget what brought us here in the first place: we needed a tactic that allowed us to reduce the size of our large PostgreSQL databases so we could scale PostgreSQL further. To show how effective Timescale compression can be for this task, the table below includes someactual exa...
Change Data Capture (CDC) can synchronize incremental changes from the source database to one or more destinations. During data synchronization, CDC processes data, for example, grouping (GROUP BY) and joining multiple tables (JOIN). This example creates a PostgreSQL CDC source table to monitor ...