Expression of String type that defines Oracle SQL hint.
It is used as an instruction for the performance optimizer of 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 given the 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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