com.ibm.websphere.ejbquery
Interface Query
- public interface Query
- extends javax.ejb.EJBObject
When using the remote interface for the query service, any references to EJB Objects in the query statement will be to remote interfaces.
For example, the ejb query statement
select object(o) from myBean o
will return references to the remote interface for myBean.
The dynamic query remote interface will create a fully materialized result set.
To create a demand driven result set use the query service local interface.
QueryLocal
To control the size of a potentially large result set, you must pass a maxRow value.
The QueryIterator has a method to determine if the result set was truncated.
QueryIterator.isComplete()
You can use skipRows to execute the query again and retrieve the next set of tuples.
For example,
// this query call will retrieve the first 100 beans executeQuery("select object(o) from myBean o", null, null, 0, 100); // this query call will retrieve the next 100 beans executeQuery("select object(o) from myBean o", null, null, 100, 100);
Method Summary
Modifier and Type | Method and Description |
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executePlan(java.lang.String queryPlan,java.lang.Object[] parameterVars,int skipRows,int maxRows)
execute a query plan that was returned by the prepareQuery method.
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executeQuery(java.lang.String queryStatement,java.lang.Object[] parameterVars,java.util.Properties queryDomain,int skipRows,int maxRows)
validate and execute an ejb query statement
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prepareQuery(java.lang.String queryStatement,java.lang.Object[] parameterVars,java.util.Properties queryDomain)
validate the ejb query statement and return a query plan in the form of a String that can be used
with the executePlan method.
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Methods inherited from interface javax.ejb.EJBObject |
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getEJBHome, getHandle, getPrimaryKey, isIdentical, remove |
Method Detail
executePlan
- QueryIterator executePlan(java.lang.String queryPlan,
- java.lang.Object[] parameterVars,
- int skipRows,
- int maxRows)
- throws java.rmi.RemoteException
- QueryException
queryPlan
- The String returned from a prepareQuery method. parameterVars
- The values to be substituted for any query parameters in the query statement.
The datatypes of the parameters must be the same as the datatypes passed in on the prepareQuery call. skipRows
- Number of tuples in the final result set to skip. maxRows
- Maximum number of tuples to return in result set. QueryException
- Indicates an invalid query plan, a server or
database error occurred, or the query invoked an application method which threw an exception. java.rmi.RemoteException
executeQuery
- QueryIterator executeQuery(java.lang.String queryStatement,
- java.lang.Object[] parameterVars,
- java.util.Properties queryDomain,
- int skipRows,
- int maxRows)
- throws java.rmi.RemoteException
- QueryException
queryStatement
- parameterVars
- The values to be substituted for any query parameters in the query statement. queryDomain
- Normally a null value. This parameter is null in the cases where the Abstract Schema Names (ASN) used in the query
statement are unique in the server scope. If ASN names are not unique across applications in the server, then
the ASN name must be qualified by its EJB Home reference. This takes the form of name/value pairs (ASN name,
EJB Home object reference). An EJB Home reference can be obtained from a name service lookup call. skipRows
- Number of tuples in the final result set to skip. maxRows
- Maximum number of tuples to return in result set. QueryException
- Indicates an invalid query plan, a server or
database error occurred, or the query invoked an application method which threw an exception. java.rmi.RemoteException
prepareQuery
- java.lang.String prepareQuery(java.lang.String queryStatement,
- java.lang.Object[] parameterVars,
- java.util.Properties queryDomain)
- throws java.rmi.RemoteException
- QueryException
queryStatement
- parameterVars
- The values to be substituted for any query parameters in the query statement.
The datatypes of the values but not the actual values are used in validating the query. queryDomain
- Normally a null value. See executeQuery(java.lang.String, java.lang.Object[], java.util.Properties, int, int)
QueryException
- Indicates an invalid query plan, a server or
database error occurred, or the query invoked an application method which threw an exception. java.rmi.RemoteException