Question

我需要执行这一询问:

SELECT MAX(col1) FROM table1;
INSERT INTO table1 (col1) VALUES (@someting);

Where @something is MAX(col1) + 1. Can you help me writing queries? I need query works also with NULL values...I think I need a CAST.

This is a drupal like table. col0 is AUTO_INCREMENT, but col1 can t for a lot of reasons.

col0是主要的关键,而自动焚化是积极的。但是,我把手法作为版本的ID。我需要加固,不增加新的记录,我需要一眼.。

Answer 1

你们不需要一个变数。你只能使用<条码>。 INSERT INTO ...... SlectT statement:

INSERT INTO table1 (col1)
  SELECT MAX(col1) + 1 FROM table1

如有必要,请将<条码>(第1栏)>改为<条码>NUL,使用<条码>COALESCE():

INSERT INTO table1 (col1)
  SELECT COLAESCE(MAX(col1) + 1, 1) FROM table1

注:如评论意见所述,如果你试图增加一栏,则没有这样做。采用适当的<条码>AUTO_INCREMENT, 否则,将不发生种族情况。

Update after comments:

你在评论中提出的问题大不相同。页: 1 而是作为:

INSERT INTO node (vid, type, uid, title, created, changed, status, promote, sticky)
  SELECT
    COALESCE(MAX(vid) + 1, 1),
     node ,
    1,
     title , 
    1,1,1,1,1
  FROM node

A proper auto-incrementing column definition for vid would look like the following, assuming it is the primary key:

vid INT NOT NULL PRIMARY KEY AUTO_INCREMENT

采用以上规定,无需填写<条码>/>/>

Update after comments:

友情链接