Problem 8 of 10 · Incremental merge & CDCNext: Apply a batch to an SCD2 dimension

00:00

Practice / SQL / Incremental merge & CDC

WorkingGuided

HardAbout 12 minIncremental merge & CDC

Find the keys that would break a MERGE

A MERGE raises "multiple source rows matched a target row" when a matched key appears more than once in the source. Identify those offending keys: keys present in tgt that src carries more than once, with the source count. Sort by k.

Returnksrc_rows

Columns

src1 column

columntype

kBIGINT

tgt1 column

columntype

kBIGINT

The tables

srcfirst 5 of 6 rows

k

1

1

2

1

2

tgt2 rows

k

1

3

If you get stuck

Show hint · 1 hint Walkthrough Reveal answer

Your query · runs in your browser⌘ Enter to run

Loading editor…

Output · run to see rows