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Showing posts with the label odi scd

Slowly Changing Dimension (SCD) with ODI

SCD Types 1) Overwrite old data with new 2) Adding a new row with surrogate key 3) Adding columns represents first, last and previous data Other: If data is big, you can take monthly snapshots to save difference. Data is smaller and you want to track multiple columns, then you can take daily snapshots. SCD type 2 is mostly prefered as keeps old versions. So let's roll on ODI for SCD type 2. Our example will be sh.channels table comes default on Oracle db; CREATE TABLE CHANNELS (   CHANNEL_ID        NUMBER                      NOT NULL,   CHANNEL_DESC      VARCHAR2(20 BYTE)           NOT NULL,   CHANNEL_CLASS     VARCHAR2(20 BYTE)           NOT NULL,   CHANNEL_CLASS_ID  NUMBER                      NOT NULL,   CHANNEL_TOTAL     ...