How to Add a New SQL Column with a Default Value of 0?

Adding a New SQL Column with a Default Value of 0

Adding a new column to a MySQL database with a default value of 0 is a simple task. Here's the syntax:

ALTER TABLE table1 ADD COLUMN foo INT DEFAULT 0;

This example adds a column named "foo" of type INT to the table "table1" and sets its default value to 0.

Reference Breakdown:

The syntax for adding a new column is:

ALTER [ONLINE | OFFLINE] [IGNORE] TABLE tbl_name
   alter_specification [, alter_specification] ...

Where "alter_specification" can be:

ADD [COLUMN] (col_name column_definition,...)

The column_definition syntax is similar to that of CREATE TABLE:

column_definition:  
   data_type [NOT NULL | NULL] [DEFAULT default_value]
   [AUTO_INCREMENT] [UNIQUE [KEY] | [PRIMARY] KEY]  
   [COMMENT 'string']  
   [COLUMN_FORMAT {FIXED|DYNAMIC|DEFAULT}]  
   [STORAGE {DISK|MEMORY|DEFAULT}]  
   [reference_definition]  

In this case, we use "INT" as the data_type and "DEFAULT 0" to specify the default value.

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