org.postgresql.core

Interface Query

All Known Implementing Classes:

BatchedQuery

public interface Query

Abstraction of a generic Query, hiding the details of any protocol-version-specific data needed to execute the query efficiently.

Query objects should be explicitly closed when no longer needed; if resources are allocated on the server for this query, their cleanup is triggered by closing the Query.

Author:

Oliver Jowett ([email protected])

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Close this query and free any server-side resources associated with it.
ParameterList	createParameterList() Create a ParameterList suitable for storing parameters associated with this Query.
int	getBatchSize() Get the number of times this Query has been batched.
String	getNativeSql() Returns SQL in native for database format.
Map<String,Integer>	getResultSetColumnNameIndexMap() Get a map that a result set can use to find the index associated to a name.
SqlCommand	getSqlCommand() Returns properties of the query (sql keyword, and some other parsing info).
Query[]	getSubqueries() Return a list of the Query objects that make up this query.
boolean	isEmpty()
boolean	isStatementDescribed()
String	toString(ParameterList parameters) Stringize this query to a human-readable form, substituting particular parameter values for parameter placeholders.

Method Detail

createParameterList

ParameterList createParameterList()

Create a ParameterList suitable for storing parameters associated with this Query.

If this query has no parameters, a ParameterList will be returned, but it may be a shared immutable object. If this query does have parameters, the returned ParameterList is a new list, unshared by other callers.

Returns:

a suitable ParameterList instance for this query

toString

String toString(ParameterList parameters)

Stringize this query to a human-readable form, substituting particular parameter values for parameter placeholders.

Parameters:

parameters - a ParameterList returned by this Query's createParameterList() method, or null to leave the parameter placeholders unsubstituted.

Returns:

a human-readable representation of this query

getNativeSql

String getNativeSql()

Returns SQL in native for database format.

Returns:

SQL in native for database format

getSqlCommand

SqlCommand getSqlCommand()

Returns properties of the query (sql keyword, and some other parsing info).

Returns:

returns properties of the query (sql keyword, and some other parsing info) or null if not applicable

close

void close()

Close this query and free any server-side resources associated with it. The resources may not be immediately deallocated, but closing a Query may make the deallocation more prompt.

A closed Query should not be executed.

isStatementDescribed

boolean isStatementDescribed()

isEmpty

boolean isEmpty()

getBatchSize

int getBatchSize()

Get the number of times this Query has been batched.

Returns:

number of times addBatch() has been called.

getResultSetColumnNameIndexMap

Map<String,Integer> getResultSetColumnNameIndexMap()

Get a map that a result set can use to find the index associated to a name.

Returns:

null if the query implementation does not support this method.

getSubqueries

Query[] getSubqueries()

Return a list of the Query objects that make up this query. If this object is already a SimpleQuery, returns null (avoids an extra array construction in the common case).

Returns:

an array of single-statement queries, or null if this object is already a single-statement query.