SQL · Theory

CEIL()()

Theory

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CEIL()()

CEIL()() (math) is a SQL idea you prove with Vikram walking through CEIL math, not with a slogan.

Do CEIL()() (math) once by hand. one CEIL math step Vikram can write from memory. Change one input. Say the new result out loud.

CEIL()() (math) exists so Vikram can keep Vikram walking through CEIL math correct in lab hour.

Use CEIL()() (math) when Vikram walking through CEIL math must stay clear. If a simpler SQL step works, use that instead.

Don’t do this with CEIL()() (math) — copy-pasting CEIL math without a dry-run. Interviewers spot it in ten seconds.

CEIL()() (math) is not a lonely heading. Vikram ties it to Vikram walking through CEIL math.

Close CEIL()() (math) with: “If I skip it, Vikram walking through CEIL math goes wrong like this: copy-pasting CEIL math without a dry-run.”

Exam tip

Say CEIL()() (math) in one breath, then one CEIL math step Vikram can write from memory, then copy-pasting CEIL math without a dry-run.

CEIL()() — sample query

-- CEIL()()
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;

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

Short notes

DefCEIL()() (math) — Vikram uses it for Vikram walking through CEIL math in lab hour.
RuleCEIL()() (math) → one CEIL math step Vikram can write from memory.
RememberCEIL()() (math) + an index (lab hour).
UseCEIL()() (math) in lab hour (Vikram walking through CEIL math).
TrapCEIL()() (math) — copy-pasting CEIL math without a dry-run.
ExCEIL()() (math) → Vikram walking through CEIL math.

-- CEIL()() 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;

CEIL()()

CEIL()() — sample query

Short notes

Questions

CEIL()()

CEIL()() — sample query

Short notes

Questions