-
Notifications
You must be signed in to change notification settings - Fork 1
/
Copy pathMapping-comps-expressions.html
72 lines (38 loc) · 3.2 KB
/
Mapping-comps-expressions.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Oracle Data Integrator (ODI) 12c Overview - Models and Datastores - Mapping Components and Expressions</title>
</head>
<h3>Oracle Data Integrator (ODI) 12<em>c</em></h3>
<ul>
<li>Mapping Components and Expressions</li></ul>
Reference: <a href="https://docs.oracle.com/middleware/1212/odi/ODIDG/mappings.htm#ODIDG1562" target="_blank"> Oracle Docs </a>
<br></br>
<b>Mappings:</b> logical and physical organization of your data sources, targets and the transformations through which the data flows from source to target.
<br></br>
<b>Mapping Compoents are divided into 2 categories:</b>
<br></br>
Projector Components: influence the attributes present in the data that flows through a mapping. It hides all attributes originating from preceding components; all succeeding components can only use attributes from the projector (ex: reusable mappings, aggregates, distincts, creating sets, dataset in a mapping)
<br></br>
Selector Components: re-use attributes from preceding components. (ex: join, lookups, filters, sorts, splits). They are represented as a round shape.
<br></br>
<b>Components:</b>
<br></br>
Datastores (DS): act as Projector Components. Source DS are read by the mapping. Target DS are elements that are loaded by the mapping.
<br></br>
Datasets: option to use as a source in a mapping. Provide logical container where you organize sources, define joins and filters through entity-relationship mechanism (vs flow mechanism used elsewere). Datasets act as selector components.
<br></br>
Reusable Mappings: can be nested. Can include datastores as sources and targets itself. Act as projector components.
<br></br>
Component Palette: You can also use the following in the mapping diagram: Expression, Aggregate, Distinct, Set, Filter, Join, Lookup, Sort, Split
<br></br>
Connections: create flow of data between mapping components. Most have input and output connectors. If it only has an input, it is a source. If it only has output connector, it is a target.
<br></br>
Staging Schemas: specify a staging area for a mapping or for a specific deployment specification of a mapping. To define a different staging area than any of the source or target datastores, you must define the correct physical and logical schemas in the mapping's execution context before creating a mapping (Topology)
<br></br>
Knowledge Modules: how data is moved from source to target in ODI.
<br></br>
Variables, Sequences and User Functions: used in mappings as expressions. Created in the project.
<br></br>
Expressions have a result type, such as VARCHAR or NUMERIC. Conditions are boolean, meaning, the result of a condition should always evaluate to TRUE or FALSE. A condition is needed for filter, join, and lookup (selector) components, while an expression is used in datastore, aggregate, and distinct (projector) components, to perform some transformation or create the attribute-level mappings.