Take your first steps into SQL Injection by understanding both the web application and back end database components. Fingerprint the database, map its structure, and surgically extract the data you need. The road to mastery is long, but with this kind of a send off, you'll get there in no time.
Lab git repo: https://gitlab.com/r00k/sql_for_hackers
CHAPTERS
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00:00 Intro and setup
01:54 Detecting SQL injection
06:23 Subverting application logic with ' or 1=1;--
12:05 Union select refresher
14:16 Mapping the database
17:15 Extracting data from other tables and DBs