How to write the default value 0 in mysql

In MySQL, the default value of a numeric type field can be set to 0. There are two methods: use the DEFAULT keyword, for example: CREATE TABLE my_table (id INT DEFAULT 0); use the NOT NULL constraint, for example :CREATE TABLE my_table (id INT NOT NULL).

How to write the default value 0 in MySQL

In MySQL, the default value of a field can be specified as a number or string. For numeric types (such as INT), to set the default value to 0, there are two main methods:

Method 1: Use the DEFAULT keyword

<code class="sql">CREATE TABLE my_table (
  id INT DEFAULT 0
);</code>

This syntax Will set the default value of field id to 0 if no value is explicitly specified.

Method 2: Use NOT NULL constraint

<code class="sql">CREATE TABLE my_table (
  id INT NOT NULL
);</code>

This syntax will force the field id to be non-null, so MySQL will automatically set the default value is 0.

Note: For string types, you can use the empty string ('') as the default value.

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