DELETE 语法

postgres=# select * from tdsql_pg;
 id |  nickname  
----+-------------
 2 | tdsql_pg好
 1 | Hello tdsql_pg
 3 | 
 4 | tdsql_pg good
(4 rows)

postgres=# delete from tdsql_pg where id=4;
DELETE 1

postgres=# delete from tdsql_pg where nickname is null;
DELETE 1
postgres=# select * from tdsql_pg;
 id |  nickname  
----+-------------
 2 | tdsql_pg好
 1 | Hello tdsql_pg
(2 rows)

postgres=# select * from tdsql_pg;
 id |  nickname  
----+-------------
 2 | tdsql_pg好
 1 | Hello tdsql_pg
(2 rows)

postgres=# set prefer_olap to on;
SET
postgres=# delete from tdsql_pg using t_appoint_col where tdsql_pg.id=t_appoint_col.id;
DELETE 1
postgres=# select * from tdsql_pg;
 id | nickname  
----+-----------
 2 | tdsql_pg好
(1 row)

postgres=# delete from tdsql_pg returning *;
 id | nickname  
----+-----------
 2 | tdsql_pg好
(1 row)

postgres=# insert into tdsql_pg select t,random()::text from generate_series(1,100000) as t;
postgres=# 	iming 
Timing is on.
postgres=# delete from tdsql_pg ;
DELETE 100000
Time: 100.808 ms

postgres=# insert into tdsql_pg select t,random()::text from generate_series(1,100000) as t;
INSERT 0 100000
Time: 13178.429 ms
postgres=# truncate table tdsql_pg;
TRUNCATE TABLE
Time: 24.242 ms