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VARCHAR

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VARCHAR

VARCHAR is a SQL idea you prove with Arun walking through VARCHAR, not with a slogan.

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

Without VARCHAR, a viva board gets messy and Arun walking through VARCHAR is hard to trust.

Use VARCHAR when Arun walking through VARCHAR must stay clear. If a simpler SQL step works, use that instead.

VARCHAR miss — only reciting the name of VARCHAR. Fix it before you talk about advanced SQL.

VARCHAR is not a lonely heading. Arun ties it to Arun walking through VARCHAR.

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

Exam tip

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

VARCHAR — sample query

-- VARCHAR
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;

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

Short notes

DefVARCHAR — Arun uses it for Arun walking through VARCHAR in a viva board.
RuleVARCHAR → one VARCHAR step Arun can write from memory.
RememberVARCHAR + InnoDB (a viva board).
UseVARCHAR in a viva board (Arun walking through VARCHAR).
TrapVARCHAR — only reciting the name of VARCHAR.
ExVARCHAR → Arun walking through VARCHAR.

-- VARCHAR 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;

VARCHAR

VARCHAR — sample query

Short notes

Questions

VARCHAR

VARCHAR — sample query

Short notes

Questions