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PG_UPDATE action


Function
Modification of existing row in specified table.
Declaration
 PG_UPDATE handleIdent_Int, pageNrIdent_Int, rowInPageIdent_Int, rowIdent, retCodeIdent_Int [ORAHINT hintIdent_Str]

Parameters
handleIdent_Int in Identifier of Int type (handle) of the connection with a table (returned by the action PG_CONNECT).
pgNrIdent_Int_Int in Identifier of Int type of the page, where the modified row is placed in.
rowInPageIdent_Int in Identifier of Int type of the serial number of a row modified on the given page.
rowIdent in One structure row identifier (new row value).
retCodeIdent_Int out Identifier of Int type - action success.
hintIdent_Str in 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.

Return code
The value of the parameter transHandle_Int. See the table of error codes. It is possible to get extended error information.
Description
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 (
WHERE
).

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