What is The Boolean Data Type? | How to use Boolean in programming?

Summary: In this article, you will learn What is The Boolean Data Type? and How to use it in programming? let’s understand this article in detail with an example.

What is The Boolean Data Type?

In computer science, a bool and boolean is the data type that can store two possible values such as true or false. It is named after the English mathematician and logician George Boole, whose algebraic & logical systems are utilized in all trendy digital computers.

.
Note: Boolean is pronounced BOOL-ee-an. The word “Boolean” ought to solely be capitalized in regard to Boolean algebra or Boolean logic. Furthermore, when referring to the data type in computer programming, the word “boolean” is correctly spelled with a lowercase b.

The SQL type BOOLEAN, which has two states: true and false. The 3rd state in SQL boolean logic is unknown, which is represented by the NULL value.

Syntax:

BOOLEAN

Parameters

In this parameters the Valid literal data values for input are as given below:
The Boolean Data Type Parameters

Important Note:

  • First thing is that don’t confuse BOOLEAN data type with Boolean Operators or the Boolean-Predicate.
  • The keywords TRUE and FALSE are preferred/most popular and are SQL-compliant.
  • A Boolean value of NULL seems last (largest) in ascending order.
  • All other/alternative values should be enclosed in single quotes.
  • Here, the Boolean values are output using the letters ‘t’ and ‘f’.

In Microsoft SQL Server

Therefore, in Microsoft SQL Server, a boolean value isn’t supported in any respect, neither as a standalone nor representable as an integer. It always shows the error message “An expression of the non-boolean type specified in a context where a condition is expected” so if a column is directly used in the SQL WHERE clause.

For Example:- SELECT a FROM t WHERE a, while a statement such as SELECT column IS NOT NULL FROM t yields a syntax error. Therefore, the BIT data type, which can only store integers 0(zero) and 1(one) except NULL, is often used as a workaround to store Boolean values, however, workarounds got to be used  UPDATE t SET flag = IIF(col IS NOT NULL, 1, 0) WHERE flag = 0 to convert between the integer & boolean expression.

Microsoft Access, which uses the Access Database Engine, also does not have a boolean data type. just like MS SQL Server, it uses a BIT data type. In Access it’s referred to as a Yes/No data type which can have 2 values Yes (True) or No (False). The BIT data type in Access can also be described numerically True is −1 and False is 0. This differs from MS SQL Server in two(2) ways, even though both are Microsoft products:

  • Access represents TRUE as −1, whereas it’s 1 in SQL Server
  • The access doesn’t support the Null tri-state, supported by SQL Server

PostgreSQL

The PostgreSQL has a distinct BOOLEAN type as in the standard, which allows predicates to be stored directly into a BOOLEAN column, and allows using a BOOLEAN column directly as a predicate in a WHERE clause.

MySQL

In MySQL, The BOOLEAN is behave as an alias of TINYINT(1), TRUE is the same as integer 1(one) and FALSE is the same as integer 0(zero). Thus, any non-zero integer is true in conditions.

Boolean Operator

A boolean operator, or logical operator, consists of operators like AND, OR, NOT, NOR, NAND, and XOR. Furthermore, these operators are used with conditional statements in programming languages, search engines, algorithms, and formulas.

The Boolean Data Type Conclusion:

you have learned Boolean Data Type and How to use it, I hope you will enjoy it!