OpenEdge Data Management: DataServer for Microsoft SQL Server

Interfacing with RDBMS stored procedures
Table 23: Options to plan the temp-table layout for result sets
To return a result set to this
type of temp-table . . . Then the layout definition is . . .
Static
Dynamic-prepared state
Note: Once the data is loaded into the temp-table, any updates made to the records
in the temp-table are not propagated back to the foreign database. Result sets
are available through temp-tables for the purpose of obtaining a snapshot of
the data. For example, you can use this technique to populate a browser from
a temp-table. You must re-read the record using the proper lock mechanism to
actually update the record.
Details about a dynamic temp-table in an unprepared state
A dynamic temp-table is considered to be in an unprepared state after the first
definitional method is called until the temp-table is prepared. If a clear dynamic
temp-table handle is passed, the DataServer populates the temp-table schema based
on the result-set schema and prepares the temp-table. A clear dynamic temp-table is
a table that is in an unprepared state where definitional methods have not yet been
called. The DataServer then executes the temp-table handle: ADD-NEW-FIELD (field
name, data type) internally for each one of the columns of the result set. If a column in
the result set from the foreign schema does not have a name (for example, an array
element field or a SQL-derived field), the DataServer assigns a name to it based on the
column position on the row.
For example, if you run the following statement, then the temp-table contains these
columns:
• Column 1
• Cust_num
• Name
• Column 4
Defined by you; you must base the layout on the
expected fields to be returned and each of these
fields’ data types so that the first field defined in
the temp-table corresponds to the first column of
the result set. This column matching and data
type matching must be repeated successfully for
each temp-table and its corresponding result set.
Dynamic - unprepared state Not defined by you; the schema of the temp-table
is based on the result-set schema and a mapping
of default OpenEdge data types for each SQL
type. For more details, see the “Details about a
dynamic temp-table in an unprepared state”
section on page 145.
/* */
SELECT “mytag,” cust_num, name, (salary * 0.10) FROM
OpenEdge Data Management: DataServer for Microsoft SQL Server 145