SQL · Theory

LOG2()()

Theory

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LOG2()()

Don’t start LOG2()() (math) with jargon. Start with LOG2 math on Dev's board. That is the whole point.

LOG2()() (math) order: meaning → one LOG2 math step Dev can write from memory → one limit. Dumping ten features helps nobody.

LOG2()() (math) exists so Dev can keep LOG2 math on Dev's board correct in a first job task.

Dev ships LOG2()() (math) in a first job task. That is the use case worth saying.

Don’t do this with LOG2()() (math) — only reciting the name of LOG2 math. Interviewers spot it in ten seconds.

After LOG2()() (math), Dev should still remember only reciting the name of LOG2 math.

One breath for LOG2()() (math), then LOG2 math on Dev's board, then only reciting the name of LOG2 math. Sit down.

Exam tip

Board: LOG2 math on Dev's board. Dry-run LOG2()() (math). Name the trap: only reciting the name of LOG2 math.

LOG2()() — sample query

-- LOG2()()
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;

LOG2()(): create two demo rows, then SELECT qty >= 2 ordered. Say which labels come back.

Short notes

DefLOG2()() (math) — Dev uses it for LOG2 math on Dev's board in a first job task.
RuleLOG2()() (math) → one LOG2 math step Dev can write from memory.
RememberLOG2()() (math) + an index (a first job task).
UseLOG2()() (math) in a first job task (LOG2 math on Dev's board).
TrapLOG2()() (math) — only reciting the name of LOG2 math.
ExLOG2()() (math) → LOG2 math on Dev's board.

-- LOG2()() 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;

LOG2()()

LOG2()() — sample query

Short notes

Questions

LOG2()()

LOG2()() — sample query

Short notes

Questions