Abstract: To provide the POS server which can respond immediately against request from local terminals, the POS server 100 according to this invention, which controls dealings of products at a plurality of stores, includes a plurality of control apparatuses 210 connecting with a plurality of local terminals 300 provided at a plurality of stores. Each of the plurality of control apparatuses 210 a dealing database 116 storing information of dealings of the products at the local terminals 300, a receiving device 152 receiving the database operating instruction for updating the dealing database 116 with the dealing of the products from the local terminal 300, and a database updating device 162 updating the dealing database 116 according to the received database operating instruction. Each receiving device 152 of the plurality of control apparatuses 210 receives the same database operating instruction which is transmitted to the control apparatuses from the local terminal 300.

Abstract: In a network-type data transmission system wherein a server 4(5) and a plurality of terminal units (client computers) 1(2,3) sharing the server 4(5) are connected by way of a network circuit 6, a packet generating means 223 of each terminal unit generates a packet command complying with a DB command transmission protocol independent of the network circuit each time the terminal unit collects data, and a packet converting means 423 of the server having received the packet command converts the packet command into a DB operation command, executes the DB operation command, and reflects an executed result on the DB, so that a demand from the terminal unit is responded in real time. With the above structure, an operation of a database server from the terminal unit is realized only by implementing a communication driver which realizes the TCP-IP, and an effective sales management system such as the POS system can be constructed.