Create a temporary table in a SELECT statement wit

问题:

Is it possible to create a temporary (session only) table from a select statement without using a create table statement and specifying each column type? I know derived tables are capable of this, but those are super-temporary (statement-only) and I want to re-use.

It would save time if I did not have to write up a create table command and keep the column list and type list matched up.

回答1:

CREATE TEMPORARY TABLE IF NOT EXISTS table2 AS (SELECT * FROM table1)

From the manual found at http://dev.mysql.com/doc/refman/5.7/en/create-table.html

You can use the TEMPORARY keyword when creating a table. A TEMPORARY table is visible only to the current session, and is dropped automatically when the session is closed. This means that two different sessions can use the same temporary table name without conflicting with each other or with an existing non-TEMPORARY table of the same name. (The existing table is hidden until the temporary table is dropped.) To create temporary tables, you must have the CREATE TEMPORARY TABLES privilege.

回答2:

In addition to psparrow\'s answer if you need to add an index to your temporary table do:

CREATE TEMPORARY TABLE IF NOT EXISTS 
  temp_table ( INDEX(col_2) ) 
ENGINE=MyISAM 
AS (
  SELECT col_1, coll_2, coll_3
  FROM mytable
)

It also works with PRIMARY KEY

回答3:

Use this syntax:

CREATE TEMPORARY TABLE t1 (select * from t2);

回答4:

Engine must be before select:

CREATE TEMPORARY TABLE temp1 ENGINE=MEMORY 
as (select * from table1)

回答5:

ENGINE=MEMORY is not supported when table contains BLOB/TEXT columns