Is it possible to call find the number of columns in a JDBC query without executing it?

From: Geoff Hardy (geoffhardynzNONE_at_hotmail.com)
Date: 02/18/04

  • Next message: Chris Smith: "Re: Is it possible to call find the number of columns in a JDBC query without executing it?" 
    Date: 18 Feb 2004 14:52:20 -0800

    Is it possible to call find the number of columns in a query without
    executing it?

    I am using the Oracle JDBC thin client driver and I have a number of
    queries for which I would like to find out how many columns are being
    selected.

    For example, if given "select a, b, from atable" there are two columns
    being selected.

    Executing the queries is likely to be expensive so I want to avoid
    that. I tried using the following code:

    PreparedStatement preparedStatement =
    connection.prepareStatement(queryStatement);
    long columnCount = preparedStatement.getMetaData().getColumnCount();

    This causes the following exception:

    java.sql.SQLException: statement handle not executed: getMetaData
    at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
    at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:179)
    at oracle.jdbc.dbaccess.DBError.check_error(DBError.java:1130)
    at oracle.jdbc.driver.OracleResultSetImpl.getMetaData(OracleResultSetImpl.java:160)
    at oracle.jdbc.driver.OraclePreparedStatement.getMetaData(OraclePreparedStatement.java:1137)

    If I call execute before calling getMetaData, this exception is not
    caused, but I would like to avoid calling execute if possible!

    Thanks in advance for any help!

  • Next message: Chris Smith: "Re: Is it possible to call find the number of columns in a JDBC query without executing it?"

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