How to set the default value to 1 in mysql

In MySQL, the default value of a column can be set to 1 using the ALTER TABLE statement and the DEFAULT keyword. The steps are as follows: 1. Determine the table name and column name; 2. Write the ALTER TABLE statement; 3. Execute the statement.

In MySQL, the default value is set to 1

In MySQL, you can pass the ALTER TABLE statement and ## The #DEFAULT keyword sets the column's default value to 1.

Syntax

<code class="sql">ALTER TABLE table_name
ALTER COLUMN column_name
SET DEFAULT 1;</code>

Steps

1. Determine the table name and column name

First, you need to know the table name to be updated Name and the name of the column for which you want to set the default value.

2. Write the ALTER TABLE statement

Use the above syntax to write the

ALTER TABLE statement, specify the table name, column name and default value.

3. Execute statement

Execute

ALTER TABLE statement in MySQL command line or client:

<code class="sql">mysql> ALTER TABLE my_table ALTER COLUMN my_column SET DEFAULT 1;</code>

Example

Suppose you have a column named

my_column in a table named my_table, and you want to set the default value of the column to 1. Then, you need to execute the following statement:

<code class="sql">ALTER TABLE my_table ALTER COLUMN my_column SET DEFAULT 1;</code>

After executing this statement, the

my_column column will default to 1 without explicitly specifying a value.

Note

The default value can be set to 1 only if the current data type of the column allows it. For example, if the column is of type string, you cannot set the default value to 1.
• If the column already has a default value, the
• ALTER TABLE statement will overwrite it.
In some cases it may be necessary to use a
• NOT NULL constraint to enforce a default value.

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