SQL · Theory

MOD()()

Theory

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MOD()()

MOD()() (math) sits in lab hour. Farhan’s job is a MOD math dry-run. Write that first.

MOD()() (math) on the board: one MOD math step Farhan can write from memory. Then say what a MOD math dry-run looks like after.

Without MOD()() (math), lab hour gets messy and a MOD math dry-run is hard to trust.

MOD()() (math) shows up in lab hour. Name a MOD math dry-run, not “a real-world scenario”.

Don’t do this with MOD()() (math) — only reciting the name of MOD math. Interviewers spot it in ten seconds.

MOD()() (math) is not a lonely heading. Farhan ties it to a MOD math dry-run.

Viva for MOD()() (math): what it is → one MOD math step Farhan can write from memory → the mistake (only reciting the name of MOD math).

Exam tip

Say MOD()() (math) in one breath, then one MOD math step Farhan can write from memory, then only reciting the name of MOD math.

MOD()() — sample query

-- MOD()()
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;

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

Short notes

DefMOD()() (math) — Farhan uses it for a MOD math dry-run in lab hour.
RuleMOD()() (math) → one MOD math step Farhan can write from memory.
RememberMOD()() (math) + the query planner (lab hour).
UseMOD()() (math) in lab hour (a MOD math dry-run).
TrapMOD()() (math) — only reciting the name of MOD math.
ExMOD()() (math) → a MOD math dry-run.

-- MOD()() 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;

MOD()()

MOD()() — sample query

Short notes

Questions

MOD()()

MOD()() — sample query

Short notes

Questions