• Do kinda like a SQL except between Old vs new ==> find exception rows
• Do SQL except between New vs Old ==> find exception rows
• For exceptions : figure out the distribution and extent of variance — for example - many a times its precision etc
• Report Total row count , row count with discrepancy
• Then same like above - column level discrepancy analysis
TestBigQuery
The comparison will essentially do something like this ( either using tool or not — but will explain Pseudo code
Updates
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