Postgresql 中文操作指南

SPI_scroll_cursor_fetch

SPI_scroll_cursor_fetch — 从游标中获取某些行

SPI_scroll_cursor_fetch — fetch some rows from a cursor

Synopsis

void SPI_scroll_cursor_fetch(Portal portal, FetchDirection direction,
                             long count)

Description

SPI_scroll_cursor_fetch 从游标中获取某些行。这等同于 SQL 命令 FETCH 。

SPI_scroll_cursor_fetch fetches some rows from a cursor. This is equivalent to the SQL command FETCH.

Arguments

  • Portal _portal_

    • portal containing the cursor

  • FetchDirection _direction_

    • one of FETCH_FORWARD, FETCH_BACKWARD, FETCH_ABSOLUTE or FETCH_RELATIVE

  • long _count_

    • number of rows to fetch for FETCH_FORWARD or FETCH_BACKWARD; absolute row number to fetch for FETCH_ABSOLUTE; or relative row number to fetch for FETCH_RELATIVE

Return Value

如果成功，则 SPI_processed 和 SPI_tuptable 与 SPI_execute 中的设置相同。

SPI_processed and SPI_tuptable are set as in SPI_execute if successful.

Notes

有关 direction 和 count 参数解释的详细信息，请参阅 SQL FETCH 命令。

See the SQL FETCH command for details of the interpretation of the direction and count parameters.

如果未使用 CURSOR_OPT_SCROLL 选项创建游标的计划，则 FETCH_FORWARD 以外の其他方向值可能会失败。

Direction values other than FETCH_FORWARD may fail if the cursor’s plan was not created with the CURSOR_OPT_SCROLL option.