Why Does `executeQuery()` Fail with INSERT, UPDATE, or DELETE Statements?

Troubleshooting "Cannot Issue Data Manipulation Statements with executeQuery()" Error

In a typical SQL database operation, you may encounter a situation where you attempt to execute queries that manipulate data, such as inserting, updating, or deleting records. However, if you use the executeQuery() method to execute these queries, you may encounter an error message stating that you cannot issue data manipulation statements with executeQuery().

Understanding the Error

executeQuery() is specifically designed to retrieve data from a database without modifying its contents. It is primarily used for queries that return result sets, such as SELECT statements. On the other hand, data manipulation statements, such as INSERT, UPDATE, and DELETE, aim to alter the database by modifying data.

Resolving the Error

To resolve this error and successfully execute data manipulation statements, you need to use the appropriate method. Instead of executeQuery(), use executeUpdate().

executeUpdate() is designed to execute SQL statements that affect data, including data manipulation operations. Here's an excerpt from the executeUpdate() documentation that provides a clear definition:

"Executes the given SQL statement, which may be an INSERT, UPDATE, or DELETE statement or an SQL statement that returns nothing, such as an SQL DDL statement."

Example

To rectify the issue described in the initial question, the code should be adjusted to use executeUpdate() as follows:

executeUpdate(query1);
executeUpdate(query2);

By using executeUpdate() for data manipulation operations, you can accurately execute the desired queries and avoid the "Cannot Issue Data Manipulation Statements with executeQuery()" error.

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