does not see effects of those commands on other rows in the database.
This behavior makes Read Committed mode unsuitable for commands that
involve complex search conditions; however, it is just right for simpler
- cases. For example, consider updating bank balances with transactions
- like:
+ cases. For example, consider transferring $100 from one account
+ to another:
<screen>
BEGIN;
COMMIT;
</screen>
- If two such transactions concurrently try to change the balance of account
- 12345, we clearly want the second transaction to start with the updated
+ If another transactions concurrently tries to change the balance of account
+ 7534, we clearly want the second statement to start with the updated
version of the account's row. Because each command is affecting only a
predetermined row, letting it see the updated version of the row does
not create any troublesome inconsistency.