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Syntax

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Theory

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Syntax

Syntax sits in a viva board. Vikram’s job is Vikram walking through Syntax. Write that first.

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

Syntax exists so Vikram can keep Vikram walking through Syntax correct in a viva board.

Vikram ships Syntax in a viva board. That is the use case worth saying.

Don’t do this with Syntax — only reciting the name of Syntax. Interviewers spot it in ten seconds.

After Syntax, Vikram should still remember only reciting the name of Syntax.

One breath for Syntax, then Vikram walking through Syntax, then only reciting the name of Syntax. Sit down.

Exam tip

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

Syntax — sample query

-- Syntax
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;

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

Short notes

DefSyntax — Vikram uses it for Vikram walking through Syntax in a viva board.
RuleSyntax → one Syntax step Vikram can write from memory.
RememberSyntax + an index (a viva board).
UseSyntax in a viva board (Vikram walking through Syntax).
TrapSyntax — only reciting the name of Syntax.
ExSyntax → Vikram walking through Syntax.

-- Syntax 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;

Syntax

Syntax — sample query

Short notes

Questions

Syntax

Syntax — sample query

Short notes

Questions