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Features

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Features

Features sits in a small live site. Rohit’s job is Rohit walking through Features. Write that first.

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

Skip Features and only reciting the name of Features shows up in a small live site.

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

Features trap — only reciting the name of Features. Rohit loses marks for that every viva.

Features is not a lonely heading. Rohit ties it to Rohit walking through Features.

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

Exam tip

Say Features in one breath, then one Features step Rohit can write from memory, then only reciting the name of Features.

Features — sample query

-- Features
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;

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

Short notes

DefFeatures — Rohit uses it for Rohit walking through Features in a small live site.
RuleFeatures → one Features step Rohit can write from memory.
RememberFeatures + the query planner (a small live site).
UseFeatures in a small live site (Rohit walking through Features).
TrapFeatures — only reciting the name of Features.
ExFeatures → Rohit walking through Features.

-- Features 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;

Features

Features — sample query

Short notes

Questions

Features

Features — sample query

Short notes

Questions