SQL选择并插入（如果不存在）

Question

I want to make an sql query which can insert into table1. This table references table2 with the table2_id foreign key.

my sql looks like this so far:

INSERT INTO table1 (table1_id, name, date, table2_id) 
VALUES (1, "somename", "29.04.2014", (SELECT id FROM table 2 WHERE table2.name = "BOB")  )

I also want to insert values into table2 if it cannot find the table2.name and then insert the key for this into table1.

Anyone knows how to do this?

Answer 1

I would suggest that you use insert . . . select insert . . . select insert . . . select rather than insert . . . values insert . . . values insert . . . values :

INSERT INTO hovedenhet (organisasjonsnummer, navn, stiftelsesdato, registreringsdatoEnhetsregisteret, organisasjonsform_id) 
    SELECT 813550202, 'SAMEIET SCHWEIGAARDSGATE 21-23', '10.01.2014', '29.04.2014', id
    FROM organisasjonsformhovedenhet oh
    WHERE oh.organisasjonsform = 'BOB';

Your original query will insert the row with a NULL value for the last column, if there is no match. This will not insert anything in that case.