INSERT with SELECT | 易学教程

问题

I have a query that inserts using a select:

INSERT INTO courses (name, location, gid) 
            SELECT name, location, gid 
              FROM courses 
             WHERE cid = $cid

Is it possible to only select \"name,location\" for the insert, and set gid to something else in the query?

回答1:

Yes, absolutely, but check your syntax.

INSERT INTO courses (name, location, gid)
SELECT name, location, 1
FROM   courses
WHERE  cid = 2

You can put a constant of the same type as gid in its place, not just 1, of course. And, I just made up the cid value.

回答2:

Yes, it is. You can write :

INSERT INTO courses (name, location, gid) 
SELECT name, location, 'whatever you want' 
FROM courses 
WHERE cid = $ci

or you can get values from another join of the select ...

回答3:

Correct Syntax: select spelling was wrong

INSERT INTO courses (name, location, gid)
SELECT name, location, 'whatever you want' 
FROM courses 
WHERE cid = $ci

回答4:

Sure, what do you want to use for the gid? a static value, PHP var, ...

A static value of 1234 could be like:

INSERT INTO courses (name, location, gid)
SELECT name, location, 1234
FROM courses
WHERE cid = $cid

回答5:

I think your INSERT statement is wrong, see correct syntax: http://dev.mysql.com/doc/refman/5.1/en/insert.html

edit: as Andrew already pointed out...

回答6:

Of course you can.

One thing should be noted however: The INSERT INTO SELECT statement copies data from one table and inserts it into another table AND requires that data types in source and target tables match. If data types from given table columns does not match (i.e. trying to insert VARCHAR into INT, or TINYINT intoINT) the MySQL server will throw an SQL Error (1366).

So be careful.

Here is the syntax of the command:

INSERT INTO table2 (column1, column2, column3)
SELECT column1, column2, column3 FROM table1
WHERE condition;

Side note: There is a way to circumvent different column types insertion problem by using casting in your SELECT, for example:

SELECT CAST('qwerty' AS CHAR CHARACTER SET utf8) COLLATE utf8_bin;

This conversion (CAST() is synonym of CONVERT() ) is very useful if your tables have different character sets on the same table column (which can potentially lead to data loss if not handled properly).

回答7:

The right Syntax for your query is:

INSERT INTO courses (name, location, gid) 
SELECT (name, location, gid) 
FROM courses 
WHERE cid = $cid

来源：https://stackoverflow.com/questions/5391344/insert-with-select

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mysql

sql

insert-select