storadbtabeller.txt

Dela stora db tabeller i små db tabeller, till exempel tre små tabeller
Relevant::::::Säkerhetskopiera först!!!::::::::::
CREATE TABLE tabell_del1 LIKE demotable;
CREATE TABLE tabell_del2 LIKE demotable;
CREATE TABLE tabell_del3 LIKE demotable;

Insert, Infoga den första tredjedelen av data i tabell_del1
INSERT INTO tabell_del1
SELECT * FROM demotable WHERE id <= (SELECT MAX(id) FROM demotable) / 3;
 
INSERT INTO tabell_del2
SELECT * FROM demotable
WHERE id > (SELECT MAX(id) FROM demotable) / 3
AND id <= (SELECT MAX(id) FROM demotable) * 2 / 3;

 
INSERT INTO tabell_del3
SELECT * FROM demotable
WHERE id > (SELECT MAX(id) FROM demotable) * 2 / 3;



Dela upp tabellen baserat på antalet rader
*** LIMIT och OFFSET  *****'
SELECT COUNT(*) FROM demotable;

CREATE TABLE tabell_del1 LIKE demotable;
CREATE TABLE tabell_del2 LIKE demotable;
CREATE TABLE tabell_del3 LIKE demotable;

INSERT INTO tabell_del1
SELECT * FROM demotable
LIMIT 30000 OFFSET 0;

INSERT INTO tabell_del2
SELECT * FROM demotable
LIMIT 30000 OFFSET 30000;

INSERT INTO tabell_del3
SELECT * FROM demotable
LIMIT 30000 OFFSET 60000;