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Queries

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Queries

Queries is a SQL idea you prove with Queries on Dev's board, not with a slogan.

Keep Queries small. Dev should finish Queries on Dev's board in a few lines, not a 40-line dump.

Without Queries, a first job task gets messy and Queries on Dev's board is hard to trust.

Queries shows up in a first job task. Name Queries on Dev's board, not “a real-world scenario”.

If Queries on Dev's board breaks under Queries, check copy-pasting Queries without a dry-run first.

Queries is not a lonely heading. Dev ties it to Queries on Dev's board.

One breath for Queries, then Queries on Dev's board, then copy-pasting Queries without a dry-run. Sit down.

Exam tip

For Queries: definition + a first job task + one failure.

Queries — sample query

-- Queries
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;

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

Short notes

DefQueries — Dev uses it for Queries on Dev's board in a first job task.
RuleQueries → one Queries step Dev can write from memory.
RememberQueries + the query planner (a first job task).
UseQueries in a first job task (Queries on Dev's board).
TrapQueries — copy-pasting Queries without a dry-run.
ExQueries → Queries on Dev's board.

-- Queries 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;

Queries

Queries — sample query

Short notes

Questions

Queries

Queries — sample query

Short notes

Questions