org.rhq.plugins.database
Class DatabaseQueryUtility

java.lang.Object
  org.rhq.plugins.database.DatabaseQueryUtility

public class DatabaseQueryUtility
extends Object

Various database (JDBC) query functions.

Author:

Greg Hinkle

Method Summary

static void	close(Statement statement, ResultSet resultSet) Closes statements and result sets.
static int	executeUpdate(DatabaseComponent databaseComponent, String query, Object... parameters) Executes a database update.
static String[]	getColumns(ResultSetMetaData rsmd) Returns an array of strings as upper-case column names.
static List<Map<String,Object>>	getGridValues(DatabaseComponent databaseComponent, String query, Object... parameters) Returns a list of values, one per row, containing a map of column names to values of that row.
static Map<String,Double>	getNumericQueryValueMap(DatabaseComponent databaseComponent, String query, Object... parameters) Returns a mapping of rows as key-value pairs where the key is the first column (a string) and the second column is a value numeric.
static Map<String,Double>	getNumericQueryValues(DatabaseComponent databaseComponent, String query, Object... parameters) Executes a query, returning the results as a map where the keys are the column names and values are the value of that column.
static Double	getSingleNumericQueryValue(DatabaseComponent databaseComponent, String query, Object... parameters) Returns the result of a query as a single Double value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

executeUpdate

public static int executeUpdate(DatabaseComponent databaseComponent,
                                String query,
                                Object... parameters)
                         throws SQLException

Executes a database update.

Parameters:

databaseComponent -

query -

parameters -

Returns:

Throws:

SQLException

getSingleNumericQueryValue

public static Double getSingleNumericQueryValue(DatabaseComponent databaseComponent,
                                                String query,
                                                Object... parameters)

Returns the result of a query as a single Double value. Returns Double.NaN if the query fails.

getNumericQueryValues

public static Map<String,Double> getNumericQueryValues(DatabaseComponent databaseComponent,
                                                       String query,
                                                       Object... parameters)

Executes a query, returning the results as a map where the keys are the column names and values are the value of that column. Note depending on the database, the column names may be uppercase (Oracle) or lowercase.

Parameters:

databaseComponent -

query - SQL query string

parameters - optional bind parameters

Returns:

a map of query results

getGridValues

public static List<Map<String,Object>> getGridValues(DatabaseComponent databaseComponent,
                                                     String query,
                                                     Object... parameters)
                                              throws SQLException

Returns a list of values, one per row, containing a map of column names to values of that row. Note depending on the database, the column names may be uppercase (Oracle) or lowercase.

Parameters:

databaseComponent - database to query

query - SQL query

parameters - parameters to bind to the query

Throws:

SQLException - if query fails

getNumericQueryValueMap

public static Map<String,Double> getNumericQueryValueMap(DatabaseComponent databaseComponent,
                                                         String query,
                                                         Object... parameters)

Returns a mapping of rows as key-value pairs where the key is the first column (a string) and the second column is a value numeric.

Parameters:

databaseComponent - the component to execute on

query - the sql query to run

parameters - any parameters to bind first

Returns:

a Map of the keys against the value

getColumns

public static String[] getColumns(ResultSetMetaData rsmd)
                           throws SQLException

Returns an array of strings as upper-case column names.

Throws:

SQLException

close

public static void close(Statement statement,
                         ResultSet resultSet)

Closes statements and result sets.