PreparedStatement interface:
- It is the extension of Statement interface.
- It is used to execute parameterized query.
- PreparedStatement improve the performance because query is compiled only once.
- For example,
- String sql=”insert into account values(?,?,?)”;
| Statement | PreparedStatement |
| It is used to execute static sql queries | It is used to execute sql statement many times. |
| Doesn’t accept input parameters | Access input parameters at runtime. |
| Statement st; st=conn.createStatement(); | PreparedStatement ps; String s=”Update Employees SET age=? WHERE id=?”; ps=conn.prepareStatement(s); |
Setter methods: PreparedStatement providing setter methods by which we can set values to query parameters.
| public void setInt(int paramIndex, int value) | Sets int value to parameter |
| public void setString(int paramIndex, String value) | Sets string value to parameter |
| public void setFloat(int paramIndex, float value) | Sets float value to parameter |
| public void setDouble(int paramIndex, double value) | Sets double value to parameter |
How to get the instance of PreparedStatement?
The prepareStatement() method of Connection interface is used to return the object of PreparedStatement.
Syntax:
public PreparedStatement prepareStatement(String query)throws SQLException
Other methods of PreparedStatement:
- public int executeUpdate() : executes the query. It is used for create, drop, insert, update, delete etc.
- public ResultSet executeQuery() : executes the select query. It returns an instance of ResultSet.