MySQL Boolean Data Types Explained

Boolean Declaration Examples

You can declare a Boolean column in MySQL using either BOOLEAN or BOOL keywords, but both are treated as TINYINT(1).

• CREATE TABLE example (is_active BOOLEAN);
• CREATE TABLE example (is_verified BOOL);

How Boolean Values Are Stored

When you insert values into a Boolean column, MySQL stores them as numeric values.

0 is stored as FALSE, and 1 is stored as TRUE.

• Inserting TRUE stores 1 in the database.
• Inserting FALSE stores 0 in the database.
• Any non-zero value is interpreted as TRUE in Boolean context.

Using Boolean Values in Queries

Boolean columns can be used in WHERE clauses and conditional expressions just like numeric columns.

Since Boolean values are stored as integers, you can use numeric comparisons or logical operators.

• SELECT * FROM users WHERE is_active = TRUE;
• SELECT * FROM users WHERE is_verified = 1;
• You can also use NOT, AND, OR with Boolean columns.

Best Practices for Boolean Data in MySQL

Although MySQL uses TINYINT(1) for Boolean, it is best to keep values strictly 0 or 1 to avoid confusion.

Use the BOOLEAN or BOOL keyword for clarity in your table definitions.

• Always insert 0 or 1 for Boolean columns.
• Avoid using other numeric values to represent TRUE.
• Use descriptive column names like is_active or has_access for Boolean fields.