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Log

Don’t start Log with jargon. Start with a Log dry-run. That is the whole point.

Log on the board — one Log step Riya can write from memory. Then say what a Log dry-run looks like after.

Log exists so Riya can keep a Log dry-run correct in a viva board.

Use Log when a Log dry-run must stay clear. If a simpler SQL step works, use that instead.

If a Log dry-run breaks under Log, check skipping the failure case for Log first.

Log is not a lonely heading. Riya ties it to a Log dry-run.

One breath for Log, then a Log dry-run, then skipping the failure case for Log. Sit down.

Exam tip

For Log: definition + a viva board + one failure.

Log — sample query

-- Log
CREATE TABLE demo (
  id INTEGER PRIMARY KEY,
  label TEXT NOT NULL,
  qty INTEGER DEFAULT 0
);
INSERT INTO demo (id, label, qty) VALUES
  (1, 'alpha', 2),
  (2, 'beta', 5);
SELECT label, qty FROM demo WHERE qty >= 2 ORDER BY qty DESC;

Log: create two demo rows, then SELECT qty >= 2 ordered. Say which labels come back.

Short notes

DefLog — Riya uses it for a Log dry-run in a viva board.
RuleLog → one Log step Riya can write from memory.
RememberLog + the query planner (a viva board).
UseLog in a viva board (a Log dry-run).
TrapLog — skipping the failure case for Log.
ExLog → a Log dry-run.

-- Log CREATE TABLE demo ( id INTEGER PRIMARY KEY, label TEXT NOT NULL, qty INTEGER DEFAULT 0 ); INSERT INTO demo (id, label, qty) VALUES (1, 'alpha', 2), (2, 'beta', 5); SELECT label, qty FROM demo WHERE qty >= 2 ORDER BY qty DESC;

Log

Log — sample query

Short notes

Questions

Log

Log — sample query

Short notes

Questions