SQL · Theory

STRCMP()()

Theory

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STRCMP()()

STRCMP()() is a SQL idea you prove with Farhan walking through STRCMP, not with a slogan.

STRCMP()() order: meaning → one STRCMP step Farhan can write from memory → one limit. Dumping ten features helps nobody.

STRCMP()() exists so Farhan can keep Farhan walking through STRCMP correct in lab hour.

Use STRCMP()() when Farhan walking through STRCMP must stay clear. If a simpler SQL step works, use that instead.

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

After STRCMP()(), Farhan should still remember only reciting the name of STRCMP.

One breath for STRCMP()(), then Farhan walking through STRCMP, then only reciting the name of STRCMP. Sit down.

Exam tip

Say STRCMP()() in one breath, then one STRCMP step Farhan can write from memory, then only reciting the name of STRCMP.

STRCMP()() — sample query

-- STRCMP()()
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;

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

Short notes

DefSTRCMP()() — Farhan uses it for Farhan walking through STRCMP in lab hour.
RuleSTRCMP()() → one STRCMP step Farhan can write from memory.
RememberSTRCMP()() + the query planner (lab hour).
UseSTRCMP()() in lab hour (Farhan walking through STRCMP).
TrapSTRCMP()() — only reciting the name of STRCMP.
ExSTRCMP()() → Farhan walking through STRCMP.

-- STRCMP()() 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;

STRCMP()()

STRCMP()() — sample query

Short notes

Questions

STRCMP()()

STRCMP()() — sample query

Short notes

Questions