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Create a temporary table in a SELECT statement without a separate CREATE TABLE

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.


m
maxhb
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.


Perfect! Columns with optimum maxlengths and all! I added the word temporary so create temporary table mytable as select ....
@imperium2335, Perhaps you should try the following: create table t as select ... limit 0; alter table t engine=memory; insert into t select .... Or, perhaps you can change the "default engine of new tables". I imagine this can be done in a session level variable. Better yet, use the Ask Question button on the upper-right.
It doesn't require knowing about the column names and types, which was the questioner's reason for wanting to avoid using Create Table.
you can use it like this CREATE TEMPORARY TABLE IF NOT EXISTS table2 LIKE table1 if you dont want to copy data, just structure
what do you mean by session ?
S
Serge S.

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


Can Engine=Memory be used too with such syntax?
@DarkSide Yes ENGINE=MEMORY can also be used. See the following example: blog.cnizz.com/2010/11/24/…
what is the difference between MyISAM and Memory engine? what are the benefits of memory?
@yeahman MyISAM engine stores data in the disk but the memory engine keeps it in RAM. P.S: the memory engine doesn't support transactions, table level locking only... read more: dba.stackexchange.com/questions/1811/…
s
shA.t

Use this syntax:

CREATE TEMPORARY TABLE t1 (select * from t2);

That's more objective for copy data! Great!
C
Crusader

Engine must be before select:

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

s
shA.t

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


P
Pete855217

As I understand it, a SELECT statement will work on the temporary table if you're using it in something like phpMyAdmin, but following that SELECT, the temporary table will be gone. This means set up exactly what you want to do with it first, and don't view any results till your 'action' statements that change the data (DELETE, UPDATE) are complete.