Troubleshooting
Problem
How CDC works - in simple terms.
Resolving The Problem
The first step is to identify the column that we use in CDC. Think of this step as adding a column to the input source, i.e.
SELECT a, b, c, d
FROM t
When you run Load Management, AW prompts you for a From and To value to append the following filter
SELECT a, b, c, d
FROM t
WHERE d >=
from-value AND d <= to-value
d can be a column from the source or a valid FM calculation that can be used to work in the WHERE BETWEEN clause. For CDC, d has to be a single value. The from-value and to-value will be adjusted by AW after each load, that is, from-value becomes the to-value + 1 sec and to-value become today's date. CDC mechanism is a sliding window. The user can change the width of the window at runtime. d can be a calculation that causes the row to be inside or outside of this window.
In a filter, it can be any expression that will work in the WHERE clause, that is, it is a condition
SELECT a, b, c
FROM t
WHERE d =
sysdate()
Historical Number
1027409
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Document Information
Modified date:
19 August 2022
UID
swg21346470