postgres=# drop table t_ret; DROP TABLE postgres=# create table t_ret(id int, info text, crt_time timestamp); CREATE TABLE postgres=# insert into t_ret values (1,’digoal’,now()), (2,’DIGOAL’,now()), (3,’digoal’,now()), (4,’abc’,now()); INSERT 0 4 postgres=# c...
ERROR: extension "mysql_fdw" alreadyexistspostgres=#CREATESERVER mysql_svrFOREIGNDATA WRAPPER mysql_fdw OPTIONS (address'127.0.0.1', port'3306');CREATESERVERpostgres=#CREATEFOREIGNTABLEexample (idINT,dataVARCHAR(100) ) SERVER mysql_svr postgres-# OPTIONS (table'mysql.example');CREATEFOREIGNTABLEpostgre...
you can access the foreign tables on the remote servers. For example, suppose there are two remote servers, namaly, postgresql and mysql, which have foreign_pg_tbl table and foreign_my_tbl table, respectively. In this exmaple, you can access the foreign tables from the local server by iss...
-- example of shard_allowed_on_node_function CREATE FUNCTION isolate_shard_10000_on_10_0_0_1(shardid bigint, nodeidarg int) RETURNS boolean AS $$ SELECT (CASE WHEN nodename = '10.0.0.1' THEN shardid = 10000 ELSE shardid != 10000 END) FROM pg_dist_node where nodeid = nodeidarg ...
CREATE FOREIGN TABLE test(a int, b text) SERVER csv OPTIONS (program 'gunzip -c /tmp/data.csv.gz'); 不依赖OS层的通用全球化支持 - ICU库 编译时,使用ICU --with-icu Build with support for the ICU library. This requires the ICU4C package to be installed. The minimum required version of...
CREATE TABLE example ( a integer, b integer, c integer, PRIMARY KEY (b, c) ); 1. 2. 3. 4. 5. 6. 外键约束声明一个字段(或者一组字段)的数值必须匹配另外一个表中某些行出现的数值。 我们把这个行为称做两个相关表之间的参考完整性。
Fixed an issue with handling of column name alias which may cause client to hang if column name alias contains string of length more than 64 bytes, for example, select col as '您对“数据一览“中的车型,颜色,内饰,选装, '. Fixed datatype of information_schema_tsql.tables.TABLE_TYPE column....
Once for a normal user (non-superuser) in PostgreSQL, as PostgreSQL superuser. It is a good idea to use a superuser only where really necessary, so let's allow a normal user to use the foreign server (this is not required for the example to work, but it's security recommendation)....
We have seen that foreign tables can be writable. PostgreSQL provides features to implement check constraints and triggers on the foreign table as well. This allows us to have powerful capabilities in the local database. For example, all validations and auditing can take place on the local serv...
postgres_fdw and the FDW feature do not support the distributed lock manager and the distributed deadlock detection feature. Therefore, a deadlock can be easily generated. For example, if Client_A updates a local table 'tbl_local' and a foreign table 'tbl_remote' and Client_B updates 'tbl...