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SQL
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Deduplication
SQL Deduplication problems
2 problems, easiest first.
Deduplicate Marketing Leads
deduplication · window-functions · strings
medium
Latest Status per Shipment
window-functions · deduplication
medium
Dates
16
Window Functions
13
Null Handling
11
Aggregation
11
Group By
8
Joins
7
Case When
6
Sorting
6
Strings
5
Subqueries
5
Select Filter
4
Running Totals
4
Ctes
3
Recursive Cte
3
Set Operations
2
Ranking
2
Deduplication
2
Self Join
2
Gaps And Islands
2