1. Research and provide three to four paragraphs covering the following: What is a subquery, and what are its basic characteristics? What (if any) differences are there between the construction of a subquery in MS Access, MS SQL Server or Oracle? What is a correlated subquery? Give an example of each type.Be sure to cite your references.
2. Based on the group E-R diagram you produced last week, create a data dictionary for your group project using Microsoft Excel. Use Page 233, Table 7.3, as a reference. Attach the data dictionary to this assignment in a single Excel document.
What is the difference between the information provided by the E-R Diagram and the data dictionary? Simply put, the data dictionary contains the data types for the physical implementation that will be done with SQL. It forms the basis for the metadata that will be used when creating the tables. An E-R diagram specializes a logical graphic model and it doesn't contain any data type or data information in a database.