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SQL Set Operators

SQL Set Operators   Traditional Set Operators: Union Compatibility:     Requirement for the traditional set operators.    Strong requirement.                         - Same number of columns.                         - Each corresponding column is compatible.                         - Positional correspondence.     Apply to similar tables by removing columns first. SQL UNION Example:           Example 1: Retrieve basic data about all university people.                     SELECT FacNo AS PerNo, FacFirstName                                      ...

You will draw an ERD diagram on ERAssistant to demonstrate certain requirements for problem (a). Then, you will extend the initial ERD for further requirements in problems (b) and (c). In problem (d), you will identify consistency errors in a given ERD diagram and redraw the ERD without the errors.

 a. Create an ERD containing the TestOrder and Specimen entity types and a 1-M relationship from Specimen to TestOrder. For each specimen collected, the database should record a unique SpecNo, SpecArea (ectocervix, cervical, or endocervical), and SpecCollMethod (thin prep or sure path). A test order contains a TONo (primary key), TOTestName, TOTestType (HPV, CT/GC, CT, or GC), and TOTestResult (positive, negative, equivocal, or failure). A specimen does not have a test order until a delay, from hours to days. If a test order produces a failure, the specimen is given a new test order and tested again until a non-failure result is obtained. A test order is created for exactly one specimen.

Answer:
Snapshot of ERD:

b. Augment your ERD from problem (a) with the Supply entity type and an M-N relationship between TestOrder and Supply. Choose a name for the relationship based on your common knowledge of test orders and supplies. A test order can use a collection of supplies (0 or more) and a supply can be used on a collection of test orders (0 or more). The Supply entity type contains SuppNo (primary key), SuppName, SuppLotNo, and SuppQOH.

Answer


c. Use the M-N equivalence rule to transform the M-N relationship in Problem (b). You should choose appropriate names for the new relationships and entity type.

Answer










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SQL Set Operators

SQL Set Operators   Traditional Set Operators: Union Compatibility:     Requirement for the traditional set operators.    Strong requirement.                         - Same number of columns.                         - Each corresponding column is compatible.                         - Positional correspondence.     Apply to similar tables by removing columns first. SQL UNION Example:           Example 1: Retrieve basic data about all university people.                     SELECT FacNo AS PerNo, FacFirstName                                      ...
  d. Insert a new row in the Location table related to the Facility row in modification problem (c). The new row should have “Door” for the location name. Query Formulation + Result Snapshot Our Official Website :  Web Conquerors  (https://www.webconquerors.com/)  Want to get digital services?  Contact US Want to know about our services?  Our Services

Correction For ERD

 d. For each consistency error in Figure 1, you should identify the consistency rule violated and suggest possible resolutions of the error. The ERD has generic names to help will concentrate on finding diagram errors rather than focusing on the meaning of the diagram. Answer:                Entity6 is violation of the Primary key rule. As there are 3 attributes from within Entity6 that are marked as primary key. Entity6 also violates the Identifying relationship rule, as there is no foreign key in the Entity6 table to identify the item from Entity7. Since this a weak entity type, the cardinality must be 1:1, which it is not. Entity2 is a violation of the Identifying relationship rule due to it not being a weak entity type when there is an identifying relationship. Our Official Website :  Web Conquerors  (https://www.webconquerors.com/)  Want to get digital services?  Contact US Want to know about our services?  ...