ODI Incremental update policy

Incremental update policy: Data consolidation with a "update key" comparison of flow data records compared to records in the target table. Records with the same "update key" will be updated when the associated columns are not, and records that do not exist in the target table will be inserted. This method is used to manipulate the recorded changes when no recording is required.

IKM compares records differently by using a method that is oriented to SQL programming instead of comparing rows by row-by-record comparisons. The most common approach to this strategy is to integrate the converted data into the i$ table, in the following steps:
① Create the i$ table and add a column called Ind_update to identify the record asis insertedStill isbe updated；
② inserts the stream data into the i$ table, all the source data is converted and inserted into the i$ table, and the ind_update is set to "I";
③ if "Recycle errors" is selected in the interface, the rejected record is added;
④ call CKM for data quality check;
⑤ Update the Ind_update column of the i$ table if the record with the same update key as the target table is marked as "U";
⑥ updates the record in table i$ ind_update to "U" again, if the column values of these records are the same as the target table, Ind_update is set to "N", then the following records are included in the i$ table:
·“ I "These records will be inserted
·“ U "These are updated
·“ N "These records are ignored
⑦ Update the target table with the records "U" in the i$ table;
⑧ uses the record of "I" in the i$ table to insert the target table.

Note:The update key must be unique, and in most cases the primary key can be used as the update key. If the primary key is a surrogate key (automatically updated), in this case the source-based column is used as the update key.
Steps to IKM Incremental update:
①create The flow table in the staging area
②determine to update (using the update key)
③determine what shouldn ' t is updated by comparing the data
④update the target with the existing records
⑤insert new records

ODI Incremental update policy