因此，我们无法进行迭代information_schema.tables，否则我们会冒险select count(*) from name_of_composite...
如果你需要获取每个表的准确行数,可以动态生成对每个表执行COUNT(*)查询的SQL语句,并执行它们。这可以通过PL/pgSQL函数或脚本语言(如Python)来实现。下面是一个使用PL/pgSQL函数的示例: sql CREATE OR REPLACE FUNCTION count_all_tables_rows() RETURNS TABLE(table_name text, row_count bigint) AS $$ DECLA...
为了便于在命令提示符下显示中文, 在创建时通过 character set gbk 将数据库字符编码指定为 gbk。创建成功时会得到 Query OK, 1 row affected(0.02 sec) 的响应。 注意: MySQL语句以分号(;)作为语句的结束, 若在语句结尾不添加分号时, 命令提示符会以 -> 提示你继续输入(有个别特例, 但加分号是一定不会错...
postgres=#SELECTn_live_tup,n_dead_tup,relnameFROMpg_stat_all_tablesWHERErelname='store';n_live_tup|n_dead_tup|relname---+---+---1|1|store(1row)--- 我们有 1 个死元组--- 手动清理“store”表postgres=#VACUUMstore;VACUUM--- 我们最终得到 0 个死元组postgres=#SELECTn_live_tup,n_dead...
'blogdb' database, otherwise you'll get the OID of the 'public' -- namespace for the database you're currently connected to. blogdb=# select to_regnamespace('public')::oid; to_regnamespace --- 2200 (1 row) -- Now let's list all the tables, indexes, etc. that live in this...
mydb=# grant select,insert,update,delete on all tables in schema public to cdb;# 此时已经有权限去查看表中内容mydb=> select * from testtable1limit10;id| tname | dno ---+---+--- 1 | myname_1 | 2 | myname_2 | 3 | myname_3...
table.column and column identifiers parse_node.c create nodes for various structures parse_oper.c handle operators in expressions parse_param.c handle Params (for the cases used in the core backend) parse_relation.c support routines for tables and column handling parse_target.c handle the result...
and pg_tables.tablename = pg_class.relname and objsubid = 0 --为0就是表的描述,其他是字段的描述 order by pg_tables.schemaname, pg_class.relname ) bb on bb."oid" = c."oid" where relname in ( select tablename from pg_tables) ...
track_io_timing还将开始收集多个视图的统计信息,包括pg_stat_database、pg_stat_all_tables、pg_stat_user_tables。此数据显示块读取(使用的 I/O)和块命中(数据已位于共享缓冲区中)。数据持续更新,通常会找与块命中相比读取块非常高的用户表。 代码语言:javascript ...
GRANT UPDATE, INSERT, SELECT, DELETE ON TABLE "GPO".count_perion_days_lottery_201912 TO "GPO_member"; GRANT SELECT ON TABLE "GPO".count_perion_days_lottery_201912 TO "MylIZ8UUIFO7KZBh1hXEnCPHqugzAm"; GRANT ALL ON TABLE "GPO".count_perion_days_lottery_201912 TO "PcHTa4478A"; ...