Hi ,
I have factory SQL and AB PLC.My question is how can i acces data from PLC. I know i have to use OPC server but can i use Inductive automation OPC UA without installing it.


No, for FactorySQL you can only use an OPC-DA server like RSLinx, Kepware or Matrikon. I would recommend using Ignition which has the SQL Bridge module. The SQL Bridge module is the same thing as FactorySQL and Ignition has built-in drivers to:

Allen-Bradley TCP
Siemens TCP
Modbus TCP

You can also connect to any other OPC-DA or OPC-UA server.

For that one i have to buy complete ignition licence which is costly then FSQL?

No, you just need the SQL Bridge module which retails for $2500.

It depends what you want to do:
Your original post looks like you may be asking how to access an AB PLC for free. You can license a copy of the Ignition OPC-UA server without any modules and use the quick client to read and write values to your AB PLC for free.

For data logging only SQL Bridge limited is $950.

From your OP I think you might also need the OPC-COM module for $350 to communicate with an OPC-DA server (if not using a 3rd party OPC-UA server like the free Ignition one, Kepware, etc).