MakeComposedBlob (open)

Compose a blob from other blobs

Syntax

LOADLIB "wh::files.whlib";

BLOB FUNCTION MakeComposedBlob(RECORD ARRAY parts)

Parameters

RECORD ARRAY parts

Parts of the new blob

BLOB data

Blob to use for this part

INTEGER64 length

Length of this part (optional)

INTEGER64 start

Start offset inside the blob of this part (optional)

Return value

BLOB

Composed blob

Description

A composed blob allows you to create a blob by concatenation of (parts) of other blobs. This blob is not a copy, but a reference to data in a parent blobs (any action that invalidates any of the parent blobs, such as closing connections to an external database, would also invalidate a composed blob).