Unit 13: Master/Detail Forms

1
Unit 13 Master/Detail Forms

• Demo View Customer Orders
• Approach 1 Using TADOTable
• Approach 2 Using TADOQuery
• Queries with Parameters
• Announcement Assignment 7

2
Demo View Customer Orders

• Approach 1 BCB creates master/detail forms
  without coding!
• bcdemos.mdb found in C\Program Files\Common
  Files\Borland Shared\Data

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Approach 1 Using TADOTable Linking
Master/Detail Tables

• In the Detail (i.e., child) table, update
• MasterSource (point to Master/Parent)
• MasterField (point to the link column)

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Approach 1 Field Link Designer

• Click ellipsis button of the MasterField property

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Approach 2 Using TADOQuery

• Set SQL strings
• select from Customer
• select from Orders
• select from Items

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Queries with Parameters

• To define parameters
• Parameters Editor
• To update the query
• Close the query
• Set the parameter field
• Re-open the query

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Approach 2 Using TADOQuery Step 1 Adding
Parameter

• In the Detail table (e.g., qryOrder)
• Parameters property
• Add new parameter / link field (e.g., CustNo)
• Update SQL propertys WHERE clause
• select from orders
• where CustNo CustNo
• Note When using TADOQuery, do not set DataSource
  property!

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Approach 2 Using TADOQuery Step 2 Code
Parameter Field

• Make parent query fields (e.g., qryCustomer)
  persistent
• In Fields Editor Add All Fields
• In the DBNavigator OnClick event
• dmDemo-gtqryOrder-gtClose()
• dmDemo-gtqryOrder-gtParameters-gt ParamByName("CustNo
  ")-gtValue dmDemo-gt qryCustomerCustNo-gtValue
• dmDemo-gtqryOrder-gtOpen()

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Approach 2 Repeat the two steps for
qryOrderDetail

• Step 1 In qryOrderDetail
• Parameters property
• Add new parameter OrderNo
• Update SQL propertys WHERE clause
• select from items
• where OrderNo OrderNo

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Approach 2 Continue Step 2 for qryOrderDetail

• Step 2
• Make parent query fields (i.e., qryOrder)
  persistent
• In the DBNavigator OnClick event
• dmDemo-gtqryOrderDetail-gtClose()
• dmDemo-gtqryOrderDetail-gtParameters-gtParamByName("O
  rderNo")-gtValue dmDemo-gtqryOrderOrderNo-gtValue
• dmDemo-gtqryOrderDetail-gtOpen()

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Your Turn

• Create your own View Customer Order
  master/detail form using TADOQuery (Approach 2)

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Assignment 7

• Assignment 7 available today
• Due in 2 weeks see Assignments page
• You cannot use Approach 1 (using TADOTable) use
  Approach 2 instead.
• Run sample program found in K\Scratch\CPAProgram(
  Co-Op)\Year 3\Programming with OOPS\Demo\Assign720
  02
• Next Week
• Adding Global Functions
• Up Down Type Controls