QRYDTA reply object (X'241B')

The distributed data management (DDM) architecture QRYDTA (query answer set data) reply object contains some or all of the answer set data that results from a query.

Format

Read syntax diagramSkip visual syntax diagramDSSHDR LLCPaibdbpcbStreamdataLLCPXLXL

Parameters

DSSHDR
The 6-byte header that contains information about the data stream structure (DSS).
LL
The length specified as a 2-byte binary integer. This length includes LL and CP.
CP
X'241B', the 2-byte codepoint of the QRYDTA reply object.
When the QRYDTA object exceeds 32767 bytes long, an extended total length field format is used to augment the normal two-byte object length. Setting the high-order bit of the x'241B' length field (LL) to 1 specifies the following:
  • An extended total length field immediately follows x'241B' and precedes its data.
  • The x'241B' length field (LL) does not include the length of the data. It includes only the length of the x'241B' (CP), length (LL), and extended total length (XLXL) fields.
  • The value of the extended total length (XLXL) field specifies only the length of the object’s data. It does not include its own length.
  • The high-order bit of the DSSHDR LL field is set to 1 to indicate the QRYDTA object is greater than 32767 in length.
aibStream
An IMS-defined data structure.

When the Open Database Manager (ODBM) services a GU or GN call, it places the aibStream data stream followed by the dbpcbStream at the beginning of each row in the QRYDTA object. The requested row data follows immediately. The concatenation of the aibdbpcbStream and data fields comprises a single row in a query row set.

dbpcbStream
An IMS-defined data structure.

When the Open Database Manager (ODBM) services a GU or GN call, it places the aibStream data stream followed by the dbpcbStream at the beginning of each row in the QRYDTA object. The requested row data follows immediately. The concatenation of the aibdbpcbStream and data fields makes up a single row in a query row set.

data
The data that follows the aibStream and dbpcbStream data structures.

Usage

The contents of the QRYDTA reply object are described by the QRYDSC reply object. Because IMS sends all of the data for a given row as if it were a single column of type Fixed Length Byte Stream, the QRYDSC information is the same for each query. Each row is made up of an aibdbpcbStream object followed by the data.