Package mondrian.spi.impl

Class JdbcStatisticsProvider

java.lang.Object

mondrian.spi.impl.JdbcStatisticsProvider

All Implemented Interfaces:

StatisticsProvider

public class JdbcStatisticsProvider
extends Object
implements StatisticsProvider

Implementation of StatisticsProvider that uses JDBC metadata calls to count rows and distinct values.

Constructor Summary

Constructors

Constructor	Description
JdbcStatisticsProvider()

Method Summary

Modifier and Type	Method	Description
long	getColumnCardinality(Dialect dialect, DataSource dataSource, String catalog, String schema, String table, String column, Execution execution)	Returns an estimate of the number of rows in a table.
long	getQueryCardinality(Dialect dialect, DataSource dataSource, String sql, Execution execution)	Returns an estimate of the number of rows returned by a query.
long	getTableCardinality(Dialect dialect, DataSource dataSource, String catalog, String schema, String table, Execution execution)	Returns an estimate of the number of rows in a table.

Methods inherited from class java.lang.Object

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

Constructor Details

JdbcStatisticsProvider

public JdbcStatisticsProvider()

Method Details

getTableCardinality

public long getTableCardinality(Dialect dialect,
 DataSource dataSource,
 String catalog,
 String schema,
 String table,
 Execution execution)

Description copied from interface: StatisticsProvider

Returns an estimate of the number of rows in a table.

Specified by:

getTableCardinality in interface StatisticsProvider

Parameters:

dialect - Dialect

dataSource - Data source

catalog - Catalog name

schema - Schema name

table - Table name

execution - Execution

Returns:

Estimated number of rows in table, or -1 if there is no estimate

getQueryCardinality

public long getQueryCardinality(Dialect dialect,
 DataSource dataSource,
 String sql,
 Execution execution)

Description copied from interface: StatisticsProvider

Returns an estimate of the number of rows returned by a query.

Specified by:

getQueryCardinality in interface StatisticsProvider

Parameters:

dialect - Dialect

dataSource - Data source

sql - Query, e.g. "select * from customers where age < 20"

execution - Execution

Returns:

Estimated number of rows returned by query, or -1 if there is no estimate

getColumnCardinality

public long getColumnCardinality(Dialect dialect,
 DataSource dataSource,
 String catalog,
 String schema,
 String table,
 String column,
 Execution execution)

Description copied from interface: StatisticsProvider

Returns an estimate of the number of rows in a table.

Specified by:

getColumnCardinality in interface StatisticsProvider

Parameters:

dialect - Dialect

dataSource - Data source

catalog - Catalog name

schema - Schema name

table - Table name

column - Column name

execution - Execution

Returns:

Estimated number of rows in table, or -1 if there is no estimate