Cost-Based Optimization of Integration Flows - Datenbanken ...

2 Preliminaries and Existing Techniques
Table 2.2: Control-Flow-Oriented Operators
Name Description Input Output Complex
Switch
Fork
Iteration
Delay
Signal
Content-based alternative with multiple
paths (if-elseif-else semantics)
Execution of multiple parallel subflows
(forklanes)
Loop over a sequence of operators
(foreach, while)
Wait until a specific timestamp or
for a specified time, respectively
Initiation of a signal, which could be
caught by a specific signal handler
(1,1) (0,0) Yes
(0,0) (0,0) Yes
(0,1) (0,0) Yes
(0,0) (0,0) No
(0,0) (0,0) No
Table 2.3: Data-Flow-Oriented Operators
Name Description Input Output Complex
Assign Value assignment of atomic or complex
(0,*) (1,1) No
objects (language: XPath)
Translation Execution of schema mappings, in (1,1) (1,1) No
the sense of message transformations
(e.g., XSLT, STX, XQuery)
Selection Filtering of tuples depending on (1,1) (1,1) No
content-based conditions
Projection Selection of attributes depending on (1,1) (1,1) No
a specific attribute list
Join
Join between two input messages (2,2) (1,1) No
w.r.t. a join condition and a join
type
Setoperation Set operations (union, intersection,
(2,2) (1,1) No
difference) of two input
messages
Split
Decomposition of a large message (1,1) (0,*) No
into multiple smaller messages
Orderby Sorting of tuples according to a (1,1) (1,1) No
specified attribute
Groupby Partitioning of tuples w.r.t. grouping
(1,1) (1,1) No
attributes and aggregate func-
tions
Window Partitioning of tuples for ranking (1,1) (1,1) No
and correlations, without grouping
Validate Validation of one input message depending
(1,1) (0,0) No
on a specific condition
Savepoint User-defined storage of UNDO/ (1,*) (0,0) No
REDO images of the input variable
Action Execution of arbitrary code snippets (0,1) (0,1) No
24