What does sql rowcount mean

ROWCOUNT in SQL is a system variable that returns the number of rows affected by the previous Transact-SQL statement. It can be used to check the execution of the statement, count the number of rows of the result set, or control the loop.

SQL ROWCOUNT Meaning

In SQL, ROWCOUNT is a system variable that represents the number of rows affected by the previous Transact-SQL statement.

use

ROWCOUNT can be used for:

• Determines whether the Transact-SQL statement has successfully updated, inserted, or deleted data.
• Count the number of rows in the result set.
• Control cycle or cycle conditions.

grammar

 <code>SELECT @@ROWCOUNT</code>

Example

 <code class="sql">-- 更新表UPDATE myTable SET name = 'John Doe' WHERE id = 1; -- 检查受影响行数SELECT @@ROWCOUNT;</code>

result:

The above example will update a row, so the value of ROWCOUNT will be 1.

Things to note

• ROWCOUNT is only applicable to data manipulation statements (DML), such as INSERT, UPDATE, and DELETE. For DDL statements (such as CREATE TABLE or ALTER TABLE), it returns 0.
• ROWCOUNT Provides the number of affected rows immediately after the statement is executed. It does not update subsequent statements.
• @@ROWCOUNT is a temporary value that will be reset to 0 when the next statement is executed.

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