如何使特定列 0

Question

CREATE TABLE ingredient
(
    inId INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
    inName VARCHAR(30),
    inSupplier VARCHAR(30),
    inPrice double,
    inStock INT,
    imageFile VARCHAR(100)
);

I want to make inStock column 0 to all rows in the table. Do I use alter or update or set?

Answer 1

You could use an update statement without a where clause:

UPDATE ingredient
SET    inStock = 0

Answer 2

For set all exists record to 0 (zero) use query:

UPDATE ingredient SET inStock = 0;

For sure default value 0 (zero) for new inserted rows alter your table as:

ALTER TABLE `ingredient` CHANGE `inStock` `inStock` INT(11) DEFAULT 0 NULL; 

or create table using:

CREATE TABLE ingredient
(
    inId INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
    inName VARCHAR(30),
    inSupplier VARCHAR(30),
    inPrice DOUBLE,
    inStock INT DEFAULT 0 NOT NULL,
    imageFile VARCHAR(100)
);