Quick Answer: What Does ExecuteQuery Return?

What is use of PreparedStatement in Java?

PreparedStatement in Java is one of several ways to execute SQL queries using JDBC API.

Java provides Statement, …

Out of these three, Statement is used for general-purpose queries, PreparedStatement is used for executing a parametric query, and CallableStatement is used for executing Stored Procedures..

What is difference between ExecuteNonQuery and executeQuery?

ExecuteReader expects to run a query command or a stored procedure that selects records. It expects to have one or more resultsets to return. ExecuteNonQuery expects to run a command, or a stored procedure, that affects the state of the specified table. …

What is the difference between ExecuteScalar and ExecuteNonQuery?

ExecuteScalar is typically used when your query returns a single value. If it returns more, then the result is the first column of the first row. … ExecuteNonQuery is typically used for SQL statements without results (e.g., UPDATE, INSERT, etc.).

Does executeUpdate commit?

commit(); No arguments are supplied to executeUpdate when they are used to execute updateSales and updateTotals ; both PreparedStatement objects already contain the SQL statement to be executed.

What is the return type of executeQuery ()?

executeQuery : Returns one ResultSet object. executeUpdate : Returns an integer representing the number of rows affected by the SQL statement. Use this method if you are using INSERT , DELETE , or UPDATE SQL statements.

Why ResultSet is used in Java?

The SQL statements that read data from a database query, return the data in a result set. The SELECT statement is the standard way to select rows from a database and view them in a result set. The java. … A ResultSet object maintains a cursor that points to the current row in the result set.

What is the return type of executeUpdate ()?

The JDBC standard states that the executeUpdate method returns a row count or 0. … For an SQL statement that can have an update count, such as an INSERT, UPDATE, DELETE, or MERGE statement, the returned value is the number of affected rows.

Which method in statement should be used to execute a DDL command?

Statement is suitable for executing DDL commands – CREATE , DROP , ALTER , and TRUNCATE in Java JDBC….Statement important methods in Java JDBC are:executeUpdate.executeQuery.executeBatch.execute.

What is SQL in Java?

SQL (Structured Query Language) is used to perform operations on the records stored in the database such as updating records, deleting records, creating and modifying tables, views, etc. SQL is just a query language; it is not a database.

How can you execute a stored procedure in the database?

To execute a stored procedure Expand the database that you want, expand Programmability, and then expand Stored Procedures. Right-click the user-defined stored procedure that you want and click Execute Stored Procedure.

What is difference between statement and PreparedStatement?

Statement will be used for executing static SQL statements and it can’t accept input parameters. PreparedStatement will be used for executing SQL statements many times dynamically. It will accept input parameters.

Which interface provides commit () & rollback () methods?

The Connection interface is a factory of Statement, PreparedStatement, and DatabaseMetaData i.e. object of Connection can be used to get the object of Statement and DatabaseMetaData. The Connection interface provide many methods for transaction management like commit(), rollback() etc.

What is executeQuery?

executeQuery(): This method is used to execute statements that returns tabular data (example select). It returns an object of the class ResultSet.

What is the difference between executeQuery () and executeUpdate ()?

executeQuery method execute statements that returns a result set by fetching some data from the database. It executes only select statements. executeUpdate method execute sql statements that insert/update/delete data at the database.

Which method is preferred for executing DML queries?

We must prefer PreparedStatement, as it is suitable for executing DML commands – SELECT, INSERT, UPDATE and DELETE. So, in this tutorial we learned how to Execute INSERT query(DML command) using java. sql. Statement’s executeUpdate method in java.

Can we use executeQuery for update?

sql. SQLException with message “executeQuery method can not be used for update”. Statement executeUpdate(String query) is used to execute Insert/Update/Delete (DML) statements or DDL statements that returns nothing. The output is int and equals to the row count for SQL Data Manipulation Language (DML) statements.

What happens if you call deleteRow () on a ResultSet object?

The deleteRow() method of the ResultSet interface deletes the current row from the ResultSet object and from the table.

How do you query in Java?

The Java source codeCreate a Java Connection to the MySQL database.Define the SELECT statement.Execute the SELECT query, getting a Java ResultSet from that query.Iterate over the ResultSet , getting the database fields (columns) from each row of data that is returned.Close the Java database connection.More items…•

Can I use same prepared statement multiple times?

Reusing a PreparedStatement Once a PreparedStatement is prepared, it can be reused after execution. You reuse a PreparedStatement by setting new values for the parameters and then execute it again.

What does executeUpdate return?

int executeUpdate(String SQL): Returns the number of rows affected by the execution of the SQL statement. Use this method to execute SQL statements, for which you expect to get a number of rows affected – for example, an INSERT, UPDATE, or DELETE statement.

Which method needs to be used to execute a DML statement using JDBC?

The DML operations of INSERT and UPDATE—that is, the write operations—are done by means of the prepareStatement() method of the Connection object created above. A call to this method takes variable bind parameters as input parameters and creates an object instance of the PreparedStatement class.