My Computer Science Journey

  Briefly summarize 5 things what you have learned in the course so far.   Database Design Principles : I have learned how relational databases are structured and designed. How data is organized into tables that have columns and the relationships between those tables. Key Types : I learned about different types of keys used in databases, such as primary keys, composite keys, and foreign keys.  Joining Tables: I learned how to perform different types of joins like natural join, left join and right join to combine data from different tables. Using SQL Workbench: I have become familiar with SQL Workbench, and using SQL commands. This has helped me practice writing queries.  ER Diagrams: I learned about ER diagrams. ER diagrams are like a flowchart that helps use see how the entities are related.  At least 3 questions you still have about databases. Joining Tables: I still have some difficulty understanding of different joins, like the left joins and right joi...

  What is an SQL view.  How is it similar to a table? In what ways is it different (think about primary keys,  insert, update, delete operations)  SQL views are like tables in that they display a restructured table columns and data types, they both contain table data just that a view is more like a virtual table.  The differences between a view an a table is that views might have issues using insert, update, and delete statements. Since primary keys from a base might not be in a view during an insert a primary key can not be null there for it is not allowed. Aggregate values in a view might be used and update or insert to the view might create a new aggerate value which the must be converted to many base tables and the conversion is undefined there for that is also restricted.  We have completed our study of SQL for this course.  This is not to imply that we have studied everything in the language.  There are many specialized features such as calc...

  SQL has the flexibility to join tables on any column(s) using any predicate (=, >, < ).    Most of the time the join will use equality between a primary and foreign key.   Think of example where joining on something other than keys would be needed.  Write the query both as an English sentence and in SQL.  If you can't think of your own example, search the textbook or internet for an example. I found the example in the last homework problem that required to look at two tables and get two different years with two different semesters. I had to create two temp tables one to hold Fall semester and year 2009 values and another table to hold Spring semester and year 2010 values. I had two join them on the course ID that both had in course id in common.   What is your opinion of SQL as a language?  Do you think it is easy to learn and use?  When translating from an English question to SQL, what kinds of questions do you find most ch...

In my first week of database management, I am enjoying it a lot. Sometimes I think I would enjoy a career creating and managing databases.  This week we learned about relational database tables, though they look very similar to spreadsheets since both use rows and columns, they have some differences. One of the most important differences is that relational database use  primary keys and foreign keys to create relationships with other tables, something that does not occur with spreadsheets. It is important to learn database management since most data is stored in databases, it is essential as a computer science student to understand the basic workings of databases. As databases touch every aspect in all sectors of computer science field.  I have a no doubts that I will be working with them later down the road in a career.