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2020-06-30 14:58:21 +08:00

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---
layout: default_docs
title: Performing Updates
header: Chapter 5. Issuing a Query and Processing the Result
resource: media
previoustitle: Using the ResultSet Interface
previous: resultset.html
nexttitle: Creating and Modifying Database Objects
next: ddl.html
---
To change data (perform an `INSERT`, `UPDATE`, or `DELETE`) you use the
`executeUpdate()` method. This method is similar to the method `executeQuery()`
used to issue a `SELECT` statement, but it doesn't return a `ResultSet`; instead
it returns the number of rows affected by the `INSERT`, `UPDATE`, or `DELETE`
statement. [Example 5.3, “Deleting Rows in JDBC”](update.html#delete-example)
illustrates the usage.
<a name="delete-example"></a>
**Example 5.3. Deleting Rows in JDBC**
This example will issue a simple `DELETE` statement and print out the number of
rows deleted.
`int foovalue = 500;`
`PreparedStatement st = conn.prepareStatement("DELETE FROM mytable WHERE columnfoo = ?");`
`st.setInt(1, foovalue);`
`int rowsDeleted = st.executeUpdate();`
`System.out.println(rowsDeleted + " rows deleted");`
`st.close();`