How to Retrieve Column Names from a java.sql.ResultSet Using Column Index?

Retrieving Column Names from java.sql.ResultSet Using Column Index

When working with java.sql.ResultSet objects, it may be necessary to retrieve the column names by their corresponding index. The ResultSet interface does not provide a direct method for this task. However, we can leverage the ResultSetMetaData object to access the column metadata, which includes the column names.

Solution

To obtain the column name for a given index, follow these steps:

1. Fetch the ResultSetMetaData object using ResultSet.getMetaData().
2. Use ResultSetMetaData.getColumnName(index) to retrieve the name of the column at the specified index.

Example

The following code example demonstrates how to retrieve column names:

ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM TABLE2");
ResultSetMetaData rsmd = rs.getMetaData();
for (int i = 1; i <= rsmd.getColumnCount(); i++) {
    String name = rsmd.getColumnName(i);
    System.out.println(name);
}

This code will print the names of all columns in the ResultSet object.

Retrieving Aliased Column Names

If you have aliased columns in your query, such as:

SELECT x AS y FROM table

You can use ResultSetMetaData.getColumnLabel() to retrieve the aliased name:

rsmd.getColumnLabel(index)

The above is the detailed content of How to Retrieve Column Names from a java.sql.ResultSet Using Column Index?. For more information, please follow other related articles on the PHP Chinese website!