ako sa pripojiť tabuľky v sql
JOINING 2 Tables in sql
SELECT X.Column_Name , Y.Column_Name2
FROM TABLES1_NAME X
INNER JOIN TABLES2_NAME Y ON X.Primary_key = Y.Foreign_key;
--FOR EXAMPLE
--GET THE FIRST_NAME AND JOB_TITLE
--USE EMPLOYEES AND JOBS TABLE
--THE RELATIONSHIP IS JOB_ID
SELECT E.FIRST_NAME , J.JOB_TITLE
FROM EMPLOYEES E
INNER JOIN JOBS J ON J.JOB_ID = E.JOB_ID;
sql pripojiť
-- Rows with ID existing in both a, b and c
-- JOIN is equivalent to INNER JOIN
SELECT a.ID, a.NAME, b.VALUE1, c.VALUE1 FROM table1 a
JOIN table2 b ON a.ID = b.ID
JOIN table3 c ON a.ID = c.ID
WHERE a.ID >= 1000;
-- ⇓ Test it ⇓ (Fiddle source link)
vnútorné pripojiť mysql
SELECT column_name(s)
FROM table1
INNER JOIN table2
ON table1.column_name = table2.column_name;
vnútorné pripojiť
INNER JOIN is used when retrieving data from
multiple tables and will return only matching data.
example=
Select P.FIRST_NAME , M.DRUG_ID
FROM PATIENTS P
INNER JOIN MEDICATIONS M ON P.PATIENTS_ID = M.PATIENTS_ID
dva vnútorné spojenia
SELECT
c.*, i.*, a.*
FROM
invoices i
INNER JOIN
client c
ON
i.clientid = c.clientid
INNER JOIN
address a
ON
a.clientid = c.clientid
WHERE
i.id = 21
Vnútorné pripojiť sql
SELECT column_name(s)
FROM table1
INNER JOIN table2
ON table1.column_name = table2.column_name;