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Wildcards

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Wildcards

Wildcards sits in lab hour. Farhan’s job is Wildcards on Farhan's board. Write that first.

Keep Wildcards small. Farhan should finish Wildcards on Farhan's board in a few lines, not a 40-line dump.

Without Wildcards, lab hour gets messy and Wildcards on Farhan's board is hard to trust.

Wildcards shows up in lab hour. Name Wildcards on Farhan's board, not “a real-world scenario”.

Wildcards miss — copy-pasting Wildcards without a dry-run. Fix it before you talk about advanced SQL.

Place Wildcards next to nearby SQL work — one Wildcards step Farhan can write from memory is the link.

Viva for Wildcards: what it is → one Wildcards step Farhan can write from memory → the mistake (copy-pasting Wildcards without a dry-run).

Exam tip

Board: Wildcards on Farhan's board. Dry-run Wildcards. Name the trap: copy-pasting Wildcards without a dry-run.

Wildcards — sample query

-- Wildcards
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;

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

Short notes

DefWildcards — Farhan uses it for Wildcards on Farhan's board in lab hour.
RuleWildcards → one Wildcards step Farhan can write from memory.
RememberWildcards + InnoDB (lab hour).
UseWildcards in lab hour (Wildcards on Farhan's board).
TrapWildcards — copy-pasting Wildcards without a dry-run.
ExWildcards → Wildcards on Farhan's board.

-- Wildcards 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;

Wildcards

Wildcards — sample query

Short notes

Questions

Wildcards

Wildcards — sample query

Short notes

Questions