| 摘要 |
Techniques are described herein for supporting efficient evaluation of pivot operations. In an embodiment, a pivoting query on a data table is received. The query identifies pivot columns, measure columns, and grouping columns. In response to receiving the query, a staging table that comprises new pivot columns, aggregated columns, and new grouping columns may be created. For each particular unique combination of values of the grouping columns and the pivot columns in the data table, stored values in the measure columns in the data table are aggregated for certain rows in the plurality of rows in the data table. Each row of the certain rows comprises the each particular unique combination of values of the grouping columns and the pivot columns in the data table. Results of aggregating are stored in the staging table. Data that has been populated in the staging table is transposed into a result set.
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