Re: Join three tables and specify criteria... I know this should be easy!

Hi all, having a bit of a brain burp day! :-)

I have

CREATE TABLE user

(

  user_id INTEGER PRIMARY KEY,

  user_name VARCHAR(25),

);

CREATE TABLE language

(

  iso_code CHAR(2) PRIMARY KEY,

  language_name VARCHAR(30)

);

CREATE TABLE user_language

(

  ul_user_id INT,

  ul_iso_code CHAR(2),

  PRIMARY KEY (ul_user_id, ul_iso_code),

  CONSTRAINT ul_user_id_fk FOREIGN KEY (ul_user_id) REFERENCES user (user_id),

  CONSTRAINT ul_iso_code_fk FOREIGN KEY (ul_iso_code) REFERENCES language (iso_code)

); 

Then I input data thus.

INSERT INTO user VALUES(1, 'Sandor');

INSERT INTO user VALUES(2, 'Gabor');

INSERT INTO language VALUES ('EN', 'English');

INSERT INTO language VALUES ('DE', 'German');

INSERT INTO user_language VALUES(1, 'EN');

INSERT INTO user_language VALUES(1, 'DE');

INSERT INTO user_language VALUES(2, 'EN');

Now, I want the user who speaks English and the German - I may need to specify 3, 4
or conceivably even 5 languages.

I have done this, but I'm stuck :-)

SELECT u.user_name, l.language_name

FROM user u

JOIN user_language ul

ON u.user_id = ul.ul_user_id

JOIN language l

ON ul.ul_iso_code = l.iso_code

this gives me

Sandor, German

Sandor, English

Gabor, English

I really want Sandor's id - that's all that really counts.

Give me the ids of all who speak 'EN' and 'DE' (or
possibly 'EN', 'DE', 'NL' and 'FR') for example.

TIA and rgs,

Paul...

--
 
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