StepWise
100+ data structures and algorithms, every step narrated with its pseudocode line and variables; step back, share as a link, embed in Canvas.
Apps / SQL Replay
SQL Replay
Watch a SELECT execute step by step, each stage narrated.
What it does
Watch a database query run one step at a time. Type a SELECT query and the app replays it stage by stage: tables join, rows that fail the filter are struck out, groups collapse, and results get sorted and trimmed, with a plain-English note at each step describing what just happened. It follows real SQL rules, including the tricky ones around missing (NULL) values. Students and teachers can paste their own data or use the built-in demo tables, and share a query with a link.
Good to know
It only replays SELECT queries, not statements that change data.
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