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Practice/Real-World Data

SQL pattern

String Functions

7 problemsin this pattern, climbing easy → medium → hard. Pick wherever you're calibrated. Read the P12 tutorial →

Easy

0 / 3 solved

Extract the domain from an email
SQL · ~6 min
NEW
Split a full name into first and last
SQL · ~7 min
NEW
Find every signup for one email address
SQL · ~4 min
NEW

Medium

0 / 2 solved

Explode a name into one row per word
SQL · ~12 min
NEW
Normalize messy whitespace in names
SQL · ~8 min
NEW

Hard

0 / 2 solved

Split phone numbers into dial code and national number
SQL · ~14 min
NEW
Collapse name variants to one identity
SQL · ~13 min
NEW