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DBMS

DBMS sits in lab hour. Farhan’s job is a DBMS dry-run. Write that first.

DBMS on the board — one DBMS step Farhan can write from memory. Then say what a DBMS dry-run looks like after.

Without DBMS, lab hour gets messy and a DBMS dry-run is hard to trust.

Use DBMS when a DBMS dry-run must stay clear. If a simpler SQL step works, use that instead.

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

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

One breath for DBMS, then a DBMS dry-run, then only reciting the name of DBMS. Sit down.

Exam tip

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

DBMS — sample query

-- DBMS
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;

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

Short notes

DefDBMS — Farhan uses it for a DBMS dry-run in lab hour.
RuleDBMS → one DBMS step Farhan can write from memory.
RememberDBMS + the query planner (lab hour).
UseDBMS in lab hour (a DBMS dry-run).
TrapDBMS — only reciting the name of DBMS.
ExDBMS → a DBMS dry-run.

-- DBMS 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;

DBMS

DBMS — sample query

Short notes

Questions

DBMS

DBMS — sample query

Short notes

Questions