Change information within a bag
The MQAI lets we change information within a bag using the mqSet* calls. We can:
- Modify data items within a bag. The index allows an individual instance of a parameter to be
replaced by identifying the occurrence of the item to be modified (see Figure 1 ).
Figure 1. Modifying a single data item 
- Delete all existing occurrences of the specified selector and add a new occurrence to the end of
the bag. (See Figure 2.) A special index value allows
all
instances of a parameter to be replaced.
Figure 2. Modifying all data items 
Note: The index preserves the insertion order within the bag but can affect the indices of other data items.
The mqSetInteger call lets you modify integer items within a bag. The mqSetInteger64 call lets you modify 64-bit integer items. The mqSetIntegerFilter call lets you modify integer filter items. The mqSetString call lets you modify character-string items. The mqSetStringFilter call lets you modify string filter items. The mqSetByteString call lets you modify byte string items. The mqSetByteStringFilter call lets you modify byte string filter items. Alternatively, we can use these calls to delete all existing occurrences of the specified selector and add a new occurrence at the end of the bag. The data item can be a user item or a system item.
For a full description of these calls, see:- mqSetInteger
- mqSetInteger64
- mqSetIntegerFilter
- mqSetString
- mqSetStringFilter
- mqSetByteString
- mqSetByteStringFilter
Parent topic: Types of data item available in the MQAI