What does whwre mean in mysql?

The WHERE clause is used to specify filter conditions in the MySQL query to filter matching records from the result set. Its syntax structure is: SELECT * FROM table_name WHERE condition;. The WHERE clause can be used to display only records that meet certain criteria, exclude unnecessary records, and group or sort query results. A condition consists of an operator and an operand, which can be a column name, a constant, or an expression. Operators include "=", "!=", ">", "<", ">=", and "<=". Multiple conditions can be connected using logical operators (AND, OR).

The meaning of the WHERE clause in MySQL

The WHERE clause is used to specify filter conditions in MySQL queries. Filter out matching records from the result set.

Structure

The syntax is as follows:

<code class="sql">SELECT * FROM table_name WHERE condition;</code>

Among them:

• ##table_name is to be queried table name.
• condition is the condition used to filter records.

Use

The WHERE clause can be used in the following scenarios:

Only display records that meet specific conditions.
Exclude unnecessary records from the result set.
Group or sort query results.

Conditions

Conditions consist of operators and operands. Operators are used to compare two values, and the operands can be column names, constants, or other expressions. Commonly used operators include:

• =: equal
• !=: not equal to
• >: greater than

• <: less than
• >=: greater than or equal to
• <=: less than or equal to

For example, to select all customers whose age is greater than 30 from the

customers table, the query is as follows:

<code class="sql">SELECT * FROM customers WHERE age > 30;## The #WHERE clause can contain multiple conditions, connected using logical operators (AND<p>, <code>OR</code>). For example, to select orders from the <code>orders</code> table with a total price greater than $100 and a status of "shipped", the query is as follows: <code><pre class="brush:php;toolbar:false"><code class="sql">SELECT * FROM orders WHERE total_price > 100 AND status = "shipped";</code>

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