use oracle Pl/sql command line I do not know which table to use here all tables

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The system must contain tables such as category(catNo,catogeryName) ,Items(itemNo,ItemName,Price,total_quantity, catNo),Items_stor_entry(entry_no number primary key,itemNo,entry_date ,quantity),

Employee (employeeNo,employeeName,job) ,branch(No,Name), Customer(customerNo,costomerName,gender) ,

,Invoice (employeeNo,customerNo,total price ,invoiceNo,InvoiceDate,branchNo )

InvoiceDeatail contain List Of Purchase Items contain detail information related to the invoice (invoiceNo,ItemNo, paidPrice, quantity)

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Create database package pointOfSal which contain the following

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F. procedure to add newItemQuantaty(itemName,newquantaty) this firstly check the existing of this item name and return item no if exists else it return -1 , then if its exists then it will add new entry to Items_stor_entry table to create new row with this itemname as new entry to store. Then increase the item total_quantity in the items table with new quantity then display message show the items new total quantity in the store else if this item not exists it will display the message no item has this name will be display .

G. procedure to add new customer invoice addInvoice(customername,employeeName,branchName,invoice_date)

then the procedure will check from the exists of customername,employeeName,BranchName by calling there check existsing function for each name and if all of them are exists then a new record will be created with total price equel to zero and the invoceno will be generated using method getNextInvoiceNo() which return the maximum +1 , then the method will display the message one record has been created with invoice No:show the generated invoiceNo her in this message else display a specific message that show the customer or employee or branch name doesnt exist please re-enter correct names