Class SqlStatisticsProvider

    • Constructor Detail

      • SqlStatisticsProvider

        public SqlStatisticsProvider()
    • Method Detail

      • 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