What does where in mysql mean?

The WHERE clause in MySQL is used to filter query results and only return records that meet the specified conditions. It limits the results through conditions, which consist of column names, comparison operators, values ​​or variables, and logical operators. The WHERE clause is mainly used to retrieve records that meet conditions, exclude records that do not meet conditions, and create subsets required for joins and subqueries.

WHERE clause: used in MySQL to filter query results

The WHERE clause is used in SQL queries Conditions to filter data and retrieve specific records from the table. It limits query results by specifying conditions and returns only records that meet the conditions.

Grammar

<code>SELECT column_list
FROM table_name
WHERE condition;</code>

Function

The WHERE clause is mainly used for the following purposes:

• Retrieve records that meet specific conditions.
• Exclude records that do not meet the conditions from the query.
• Create more specific subsets for joins and subqueries.

Conditions

Conditions are expressions in the WHERE clause that specify filter conditions. A condition can be composed of the following elements:

• Column name or expression
• Comparison operators (such as =, <, >)
• Value or variable
• Logical operators (such as AND, OR)

Example

The following query retrieves all from the customers table Customers whose names begin with "John":

<code>SELECT *
FROM customers
WHERE name LIKE 'John%';</code>

The following query retrieves all orders greater than $100 from the orders table:

<code>SELECT *
FROM orders
WHERE amount > 100;</code>

WHERE clause for the database It is crucial to retrieve specific data. It provides powerful mechanisms to filter and limit query results, returning only records that meet given conditions.

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