有没有办法将查询应用于mysql数据库中的每个表?
就像是
SELECT count(*) FROM {ALL TABLES}
-- gives the number of count(*) in each Table
和
DELETE FROM {ALL TABLES}
-- Like DELETE FROM TABLE applied on each Table
最佳答案
select sum(table_rows) as total_rows
from information_schema.tables
where table_schema = 'your_db_name'
要注意这只是一个近似值
要删除所有表格的内容,您可以执行以下操作
select concat('truncate ',table_name,';')
from information_schema.tables
where table_schema = 'your_db_name'
然后运行此查询的输出.
UPDATE.
这是将truncate table应用于特定数据库中的所有表的存储过程
delimiter //
drop procedure if exists delete_contents //
create procedure delete_contents (in db_name varchar(100))
begin
declare finish int default 0;
declare tab varchar(100);
declare cur_tables cursor for select table_name from information_schema.tables where table_schema = db_name and table_type = 'base table';
declare continue handler for not found set finish = 1;
open cur_tables;
my_loop:loop
fetch cur_tables into tab;
if finish = 1 then
leave my_loop;
end if;
set @str = concat('truncate ',tab);
prepare stmt from @str;
execute stmt;
deallocate prepare stmt;
end loop;
close cur_tables;
end; //
delimiter ;
call delete_contents('your_db_name');