In sql, which one is executed first, where or orderby?

The WHERE statement is used to filter data and is executed first; while the ORDER BY statement is used to sort and then execute. The order is: 1. The WHERE statement filters records that meet the conditions; 2. The ORDER BY statement matches the records in the specified order. Records are sorted according to the conditions.

The execution order of WHERE statement and ORDER BY statement in SQL

In SQL query, the WHERE statement and The execution sequence of the ORDER BY statement is as follows:

1. WHERE statement

The WHERE statement is used to filter data according to specific conditions and return records that meet the conditions. It filters the rows from the table that meet the specified criteria and excludes the rows that do not meet the criteria.

2. ORDER BY statement

The ORDER BY statement is used to sort data. It will arrange the records that meet the WHERE statement conditions in the specified column and order. If no WHERE statement is specified, the ORDER BY statement sorts the entire table.

Execution Sequence Example

For example, consider the following query:

<code class="sql">SELECT * FROM customers WHERE age > 25 ORDER BY name ASC;</code>

This query will:

1. Use the WHERE statement Filter out customers older than 25 from the customers table.
2. Use the ORDER BY statement to sort qualifying customer records in ascending order by customer name.

Therefore, the WHERE statement is executed first to filter out the records that meet the conditions, and then the ORDER BY statement sorts these records.

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