Do changes made within one transaction "see" each other?

Question

Suppose I do the following set of SQL queries (pseudocode) in a table with only one column CITY:

BEGIN TRANSACTION;
INSERT INTO MyTable VALUES( 'COOLCITY' );
SELECT * FROM MyTable WHERE ALL;
COMMIT TRANSACTION;

is the SELECT guaranteed to return COOLCITY?

Answer 1

Yes.

The INSERT operation would take an X lock out on at least the newly added row. This won't get released until the end of the transaction thus preventing a concurrent transaction from deleting or updating this row.

A transaction is not blocked by its own locks so the SELECT would return COOLCITY.