borland Packages Class Hierarchy dx.sql.dataset Package
java.lang.Object +----com.borland.dx.dataset.Provider +----com.borland.dx.sql.dataset.JdbcProvider +----com.borland.dx.sql.dataset.QueryProvider
Constructors Properties Methods
Implements Designable, LoadCancel, ConnectionUpdateListener, Task, Serializable, EventListener
The QueryProvider
component is used to provide data to a DataSet
by running a query through JDBC. This component is also a place holder for static methods for executing statements with parameters (see executeStatement()
).
For information on performance tuning when executing queries, see "Fine tuning query performance" in the About section of the QueryDataSet
component.
public QueryProvider()Creates a
QueryProvider
object.
public ReadWriteRow getParameterRow() public void setParameterRow(ReadWriteRow value)The
ReadWriteRow
that is used to fill in parameter values for parameterized queries or stored procedures for StorageDataSet
extensions such as QueryDataSet
and ProcedureDataSet
.
For more information on using a ReadWriteRow
for parameters, see "Using parameterized queries to obtain data from your database" in Developing Database Applications Guide.
public final QueryDescriptor getQuery() public final void setQuery(QueryDescriptor queryDescriptor)The
QueryDescriptor
object that contains query properties.
public void checkMasterLink(StorageDataSet dataSet, MasterLinkDescriptor masterLink)Validates the
masterLink
property.
When the MasterLinkDescriptor's
fetchAsNeeded
property is enabled (true),
this method checks if there is a WHERE clause in the query.
If no WHERE clause is specified, a DataSetException
is thrown.
public static final int executeStatement(Database database, String statement, ReadWriteRow parameters)Executes the SQL statement specified as
statement
and passes values to the parameter markers in the SQL statement (all named or unnamed) with values from the ReadWriteRow
. Use this method to execute SQL statements with parameters that do not yield a ResultSet
. For example:
QueryProvider.executeStatement(db1,"INSERT INTO CUST VALUES (?,?)", paramRow);
database
Database
object associated with the query.
statement
parameters
ReadWriteRow
implementation that stores values for the query parameters.
For more information on other methods that execute statements, see "Executing queries" in the "About" section of the QueryDescriptor
class.
public static final int executeStatement(Database database, String statement, ReadWriteRow[] parameters)Similar to executeStatement(com.borland.dx.sql.dataset.Database, java.lang.String, com.borland.dx.dataset.ReadWriteRow), but allows for an array of query parameters.
database
Database
object associated with the query.
statement
parameters
ReadWriteRow
objects that store values for the query parameters. For example,
QueryProvider.executeStatement(db1,"INSERT INTO CUST (FIRST_NAME,LAST_NAME) VALUES (:1.NAME,:2.NAME)", new ReadWriteRow[] {paramRow1,paramRow2});
Where tags "1." and "2." in front of the named parameter specifies which query parameter row to find the value from. If no tags are given, the parameter names are found by searching the parameter rows from left to right.
public final String getQueryString(StorageDataSet sds)Returns the query
String
associated with this QueryDataSet
.
This property is a short cut to the
queryString
property of the QueryDescriptor
object.