MySQL表的維護(hù)和改造_MySQL

MySQL表的維護(hù)和改造

改變列的數(shù)據(jù)類型

[sql]

ALTER TABLE visitor MODIFY nam VARCHAR(30);

追加新列

[sql]

ALTER TABLE visitor ADD age INT;

ALTER TABLE visitor ADD age INT FIRST;

ALTER TABLE visitor ADD age INT AFTER nam;

改變列的位置

[sql]

ALTER TABLE visitor MODIFY age INT AFTER nam;

改變列名 和 類型

[sql]

ALTER TABLE visitor CHANGE birth birthday DATE;

刪除列

[sql]

ALTER TABLE visitor DROP age;

表的復(fù)制

[sql]

CREATE TABLE customerH SELECT * FROM customer;

CREATE TABLE customerG LIKE customer;

INSERT INTO customerG SELECT * FROM customer;

INSERT INTO tb1G(no) SELECT bang FROM tb1;

表的刪除

[sql]

DROP TABLE IF EXISTS customerG;

DROP TABLE customerG;

聲明：本網(wǎng)頁(yè)內(nèi)容旨在傳播知識(shí)，若有侵權(quán)等問(wèn)題請(qǐng)及時(shí)與本網(wǎng)聯(lián)系，我們將在第一時(shí)間刪除處理。TEL:177 7030 7066 E-MAIL:11247931@qq.com