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RLIKE

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RLIKE

Don’t start RLIKE with jargon. Start with Farhan walking through RLIKE. That is the whole point.

For RLIKE, an index is in play. Don’t blame it until you have traced Farhan walking through RLIKE.

Without RLIKE, a campus project gets messy and Farhan walking through RLIKE is hard to trust.

RLIKE shows up in a campus project. Name Farhan walking through RLIKE, not “a real-world scenario”.

If Farhan walking through RLIKE breaks under RLIKE, check copy-pasting RLIKE without a dry-run first.

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

One breath for RLIKE, then Farhan walking through RLIKE, then copy-pasting RLIKE without a dry-run. Sit down.

Exam tip

Board: Farhan walking through RLIKE. Dry-run RLIKE. Name the trap: copy-pasting RLIKE without a dry-run.

RLIKE — sample query

-- RLIKE
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;

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

Short notes

DefRLIKE — Farhan uses it for Farhan walking through RLIKE in a campus project.
RuleRLIKE → one RLIKE step Farhan can write from memory.
RememberRLIKE + an index (a campus project).
UseRLIKE in a campus project (Farhan walking through RLIKE).
TrapRLIKE — copy-pasting RLIKE without a dry-run.
ExRLIKE → Farhan walking through RLIKE.

-- RLIKE 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;

RLIKE

RLIKE — sample query

Short notes

Questions

RLIKE

RLIKE — sample query

Short notes

Questions