Expression of the String type that defines Oracle SQL hint. It is used as an instruction for the performance optimizer of the SQL command. The value is used without the opening and terminating characters /*+ <orahint> */. The example is mentioned here.
Table must be opened with the access _DB_MODIFY. The action will modify a row given by the serial number (the identifier rowInPageIdent_Int, numbering from 1 ...) on a page with the given serial number (the identifier pageNrIdent_Int, numbering from 1...).
For using the function on Microsoft SQL Server platform, there must be defined the primary key or at least unique index for a table from the platform. For the platform Sybase and Oracle, the function works without these limitations.
Warning
If the row position (page, row in a page) is given by the ordering (the clause ORDER BY) and a change will influence items determining this ordering, the row may, using the action PG_UPDATE, change its position. The similar feature occurs also in regarding to the condition of a row selection (
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