# DB architecture ```mermaid --- title: Example Git diagram --- gitGraph commit commit branch develop checkout develop commit commit checkout main merge develop commit commit ``` ```mermaid C4Context title System Context diagram for Internet Banking System Enterprise_Boundary(b0, "BankBoundary0") { Person(customerA, "Banking Customer A", "A customer of the bank, with personal bank accounts.") Person(customerB, "Banking Customer B") Person_Ext(customerC, "Banking Customer C", "desc") Person(customerD, "Banking Customer D", "A customer of the bank, <br/> with personal bank accounts.") System(SystemAA, "Internet Banking System", "Allows customers to view information about their bank accounts, and make payments.") Enterprise_Boundary(b1, "BankBoundary") { SystemDb_Ext(SystemE, "Mainframe Banking System", "Stores all of the core banking information about customers, accounts, transactions, etc.") System_Boundary(b2, "BankBoundary2") { System(SystemA, "Banking System A") System(SystemB, "Banking System B", "A system of the bank, with personal bank accounts. next line.") } System_Ext(SystemC, "E-mail system", "The internal Microsoft Exchange e-mail system.") SystemDb(SystemD, "Banking System D Database", "A system of the bank, with personal bank accounts.") Boundary(b3, "BankBoundary3", "boundary") { SystemQueue(SystemF, "Banking System F Queue", "A system of the bank.") SystemQueue_Ext(SystemG, "Banking System G Queue", "A system of the bank, with personal bank accounts.") } } } BiRel(customerA, SystemAA, "Uses") BiRel(SystemAA, SystemE, "Uses") Rel(SystemAA, SystemC, "Sends e-mails", "SMTP") Rel(SystemC, customerA, "Sends e-mails to") UpdateElementStyle(customerA, $fontColor="red", $bgColor="grey", $borderColor="red") UpdateRelStyle(customerA, SystemAA, $textColor="blue", $lineColor="blue", $offsetX="5") UpdateRelStyle(SystemAA, SystemE, $textColor="blue", $lineColor="blue", $offsetY="-10") UpdateRelStyle(SystemAA, SystemC, $textColor="blue", $lineColor="blue", $offsetY="-40", $offsetX="-50") UpdateRelStyle(SystemC, customerA, $textColor="red", $lineColor="red", $offsetX="-50", $offsetY="20") UpdateLayoutConfig($c4ShapeInRow="3", $c4BoundaryInRow="1") ```