SQL · Theory

str_to_date()

Theory

247/439

str_to_date()

str_to_date() is simple if you keep it on paper. Ananya uses it for str_to_date on Ananya's board in a viva board.

Do str_to_date() once by hand. one str_to_date step Ananya can write from memory. Change one input. Say the new result out loud.

str_to_date() exists so Ananya can keep str_to_date on Ananya's board correct in a viva board.

Use str_to_date() when str_to_date on Ananya's board must stay clear. If a simpler SQL step works, use that instead.

str_to_date() miss — copy-pasting str_to_date without a dry-run. Fix it before you talk about advanced SQL.

After str_to_date(), Ananya should still remember copy-pasting str_to_date without a dry-run.

One breath for str_to_date(), then str_to_date on Ananya's board, then copy-pasting str_to_date without a dry-run. Sit down.

Exam tip

Board: str_to_date on Ananya's board. Dry-run str_to_date(). Name the trap: copy-pasting str_to_date without a dry-run.

str_to_date() — sample query

-- str_to_date()
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;

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

Short notes

Defstr_to_date() — Ananya uses it for str_to_date on Ananya's board in a viva board.
Rulestr_to_date() → one str_to_date step Ananya can write from memory.
Rememberstr_to_date() + InnoDB (a viva board).
Usestr_to_date() in a viva board (str_to_date on Ananya's board).
Trapstr_to_date() — copy-pasting str_to_date without a dry-run.
Exstr_to_date() → str_to_date on Ananya's board.

-- str_to_date() 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;

str_to_date()

str_to_date() — sample query

Short notes

Questions

str_to_date()

str_to_date() — sample query

Short notes

Questions