What Are SQL Operators: Overview, Benefits, Use cases, and More

What Is an SQL operator?

An operator is a reserved word or a character that is used to query our database in a SQL expression. To query a database using operators, we use a WHERE clause. Operators are necessary to define a condition in SQL, as they act as a connector between two or more conditions. The operator manipulates the data and gives the result based on the operator’s functionality.

What Are the Types of SQL Operators?

Generally, there are three types of operators that are used in SQL.

1. Arithmetic Operators
2. Comparison Operators
3. Logical Operators

Now, let’s look at each one of them in detail.

1. Arithmetic SQL Operators

Arithmetic operators are used to perform arithmetic operations such as addition, subtraction, division, and multiplication. These operators usually accept numeric operands. Different operators that come under this category are given below-

2. Comparison SQL Operators

Comparison operators in SQL are used to check the equality of two expressions. It checks whether one expression is identical to another. Comparison operators are generally used in the WHERE clause of a SQL query. The result of a comparison operation may be TRUE, FALSE or UNKNOWN. When one or both the expression is NULL, then the operator returns UNKNOWN. These operators could be used on all types of expressions except expressions that contain a text, ntext or an image. The table below shows different types of comparison operators in SQL:

3. Logical SQL Operators

Logical operators are those operators that take two expressions as operands and return TRUE or False as output. While working with complex SQL statements and queries, comparison operators come in handy and these operators work in the same way as logic gates do. Different logical operations available in SQL are given in the below table.

Now, that we have learned about what an operator is and its different types such as arithmetic, comparison, and logical operators, you must be curious to see how these actually work in SQL queries. Check out Simplilearn’s SQL certification training and get yourself enrolled for mastering SQL thoroughly, starting now!