MI_COLL_DESC *mi_collection_open(conn, coll_ptr, control)
   MI_CONNECTION *conn;
   MI_COLLECTION *coll_ptr;
   mi_integer control;

conn

is a pointer to a connection descriptor established by a previous call to mi_open( ), mi_server_connect( ), or mi_server_reconnect( ).

coll_ptr

is a pointer to the collection structure to open.

control

is a bit-mask integer value that specifies the type of collection cursor to create and open. The following bit-mask flags are valid:

MI_COLL_READONLY

Cursor is read-only.

MI_COLL_NOSCROLL

Cursor is a sequential cursor (not a scroll cursor).

Valid in Client LIBMI Application?	Valid in User-Defined Routine?
Yes	Yes

The mi_collection_open_with_options( ) function is a constructor function for the collection descriptor. The function opens the collection that coll_ptr references and returns a collection descriptor for the open collection. Other DataBlade API collection functions use this collection descriptor to access the elements of a collection.

This function creates a collection cursor to hold the collection elements. By default, this cursor is an update scroll cursor. If this type of cursor is not adequate for your DataBlade API module, you can create a collection cursor with characteristics specified by a bit mask in the control argument.

Collection Cursor Type

Control-Flag Value

Update scroll cursor

None (default)

Read-only scroll cursor

MI_COLL_READONLY

Update sequential cursor

MI_COLL_NOSCROLL

Read-only sequential cursor

MI_COLL_READONLY + MI_COLL_NOSCROLL

This function is useful for accessing collection subqueries.

An MI_COLL_DESC pointer

is the address of the collection descriptor for the opened collection.

NULL

indicates that the function was not successful.

See also the descriptions of mi_collection_close( ), mi_collection_copy( ), mi_collection_create( ), mi_collection_delete( ), mi_collection_fetch( ), mi_collection_free( ), mi_collection_insert( ), mi_collection_open( ), mi_collection_update( ), mi_open( ), mi_server_connect( ), and mi_server_reconnect( ).

For a description of collections, see the IBM Informix: DataBlade API Programmer's Guide.