Transfer hangs waiting for lock

Code reviewDatabases & SQLConcurrencySenior–Staff~30 min

Review this Python (psycopg2) money-transfer function.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix, specific and kind.

0:00 of about 30 min

Mark a line and say what kind of problem it is.0 findings

1def transfer(conn, src, dst, amt):

2 with conn: # transaction

3 cur = conn.cursor()

4 cur.execute(

5 "UPDATE accounts SET balance = balance - %s WHERE id = %s",

6 (amt, src))

7 cur.execute(

8 "UPDATE accounts SET balance = balance + %s WHERE id = %s",

9 (amt, dst))

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