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FROM

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FROM

FROM sits in a campus project. Dev’s job is a FROM dry-run. Write that first.

For FROM, InnoDB is in play. Don’t blame it until you have traced a FROM dry-run.

FROM exists so Dev can keep a FROM dry-run correct in a campus project.

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

FROM trap — skipping the failure case for FROM. Dev loses marks for that every viva.

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

Viva for FROM — what it is → one FROM step Dev can write from memory → the mistake (skipping the failure case for FROM).

Diagram

  FROM students
        │
        ▼
  WHERE city = 'Pune'
        │
        ▼
  SELECT name, marks

Exam tip

Say FROM in one breath, then one FROM step Dev can write from memory, then skipping the failure case for FROM.

FROM — sample query

CREATE TABLE employees (id INTEGER PRIMARY KEY, name TEXT, dept TEXT, salary INTEGER);
INSERT INTO employees VALUES
  (1, 'Asha', 'Eng', 70000),
  (2, 'Ravi', 'Eng', 65000),
  (3, 'Neha', 'HR', 50000);
SELECT name, salary FROM employees WHERE dept = 'Eng' ORDER BY salary DESC;

FROM — sELECT projects columns; WHERE filters; ORDER BY sorts.

Short notes

DefFROM — Dev uses it for a FROM dry-run in a campus project.
RuleFROM → one FROM step Dev can write from memory.
RememberFROM + InnoDB (a campus project).
UseFROM in a campus project (a FROM dry-run).
TrapFROM — skipping the failure case for FROM.
ExFROM → a FROM dry-run.

CREATE TABLE employees (id INTEGER PRIMARY KEY, name TEXT, dept TEXT, salary INTEGER); INSERT INTO employees VALUES (1, 'Asha', 'Eng', 70000), (2, 'Ravi', 'Eng', 65000), (3, 'Neha', 'HR', 50000); SELECT name, salary FROM employees WHERE dept = 'Eng' ORDER BY salary DESC;

FROM

FROM — sample query

Short notes

Questions

FROM

FROM — sample query

Short notes

Questions