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CAST

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CAST

CAST sits in a campus project. Vikram’s job is CAST on Vikram's board. Write that first.

CAST order — meaning → one CAST step Vikram can write from memory → one limit. Dumping ten features helps nobody.

Without CAST, a campus project gets messy and CAST on Vikram's board is hard to trust.

CAST shows up in a campus project. Name CAST on Vikram's board, not “a real-world scenario”.

CAST miss — skipping the failure case for CAST. Fix it before you talk about advanced SQL.

After CAST, Vikram should still remember skipping the failure case for CAST.

One breath for CAST, then CAST on Vikram's board, then skipping the failure case for CAST. Sit down.

Exam tip

Board: CAST on Vikram's board. Dry-run CAST. Name the trap: skipping the failure case for CAST.

CAST — sample query

-- CAST
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;

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

Short notes

DefCAST — Vikram uses it for CAST on Vikram's board in a campus project.
RuleCAST → one CAST step Vikram can write from memory.
RememberCAST + an index (a campus project).
UseCAST in a campus project (CAST on Vikram's board).
TrapCAST — skipping the failure case for CAST.
ExCAST → CAST on Vikram's board.

-- CAST 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;

CAST

CAST — sample query

Short notes

Questions

CAST

CAST — sample query

Short notes

Questions