# Database Theory – Determine if a schedule is serializable or not

I'm not sure I understand the different types of schedules. I have that a schedule is a sequence of transaction operations. A serial schedule is a schedule in which transactions are executed one after the other. A serial program is when each time the transactions are executed sequentially, in some order, you could have left the database in the same state as the actual program. Finally, a serializable conflict programming is one in which the order of the transaction operations can be changed so that the programming is serial at the same time that it produces the same result.

If I have the following schedule $$R_1 (A), R_2 (B), W_1 (B), R_2 (A), W_1 (A), R_2 (B), R_2 (A)$$, there is a non-repeatable reading happening as $$T_2$$ will read different values ​​for $$A$$ Y $$B$$, then the schedule is conflictive in series because we can change the order of operations so that the schedule is serial but, how can I determine if the schedule is serializable or not?