The difference between in and = in sql

In SQL IN and = are different operators used to compare values. IN is used to check if a value belongs to a specific set of values, while = is used to compare two separate values.

The difference between IN and = in SQL

Direct answer:

IN and = are different operators used in SQL to compare values.

Detailed explanation:

1. Syntax

• IN: Compares a value to a range of values ​​to determine whether the value is in the range. The syntax is:

  SELECT * FROM table_name WHERE column_name IN (value1, value2, ..., valueN);

• =: Compares two separate values ​​for equality. The syntax is:

  SELECT * FROM table_name WHERE column_name = value;

##2. Usage

• IN: Used to check a value Belongs to a specific set of values. For example, to find all customers between the ages of 20 and 30:

  SELECT * FROM customers WHERE age IN (20, 21, 22, ..., 30);

• =: Used to compare two separate values. For example, to find customers matching a specific ID:

  SELECT * FROM customers WHERE customer_id = 12345;

3. Performance

For small data sets, the performance difference between IN and = is not significant big. However, for large data sets, IN generally performs better than = because it can compare multiple values ​​in a single query, whereas = requires multiple queries to be executed.

4. Readability

The = operator is often more readable for a smaller number of values. However, for comparing large numbers of range values, the IN operator may be easier to read and understand.

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