A database is an organized collection. of information, usually with one central topic. In a computer. database (as opposed to a paper database), the program that. you use to enter and manipulate the data is either a database..
How Many Types of Databases Are There?
Hierarchical Databases. Developed in the 1960s, the hierarchical database looks similar to a family tree. Relational Databases. Relational databases are a system designed in the 1970s. Non-Relational Databases. Object oriented databases.
Exercise 1: Selecting All Columns from A Table
Exercise: Select all data from the table distribution_companies. Solution: Solution explanation: Select the data using the SELECT statement. To select all the columns, use an asterisk (*). The table from which the data is selected is specified in the FROMclause. Solution output:
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Exercise 2: Selecting A Few Columns from A Table
Exercise:For each movie, select the movie title, the IMDb rating, and the year the movie was released. Solution: Solution explanation: List all the columns needed (movie_title, imdb_rating, and year_released) in the SELECT statement, separated by the comma. Reference the table movies in the FROMclause. Solution output:
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Exercise 3: Selecting A Few Columns and Filtering Numeric Data in Where
Exercise: Select the columns movie_title and box_office from the table movies. Show only movies with earnings above $300 million. Solution: Solution explanation: List the columns in SELECT and reference the table in FROM. Use a WHERE clause to filter the data – write the column box_office and use the ‘greater than’ operator (>) to show only values .
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Exercise 8: Grouping Data by Multiple Columns
Exercise:Show the count of movies by year released and language. Sort results by the release date in ascending order. Solution: Solution explanation: List the columns year_released and language from the table movies in SELECT. Use COUNT(*) to count the number of movies and give this column a name using the AS keyword. Specify the columns by which y.
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Exercise 9: Filtering Data After Grouping
Exercise:Show the languages spoken and the average movie budget by language category. Show only the languages with an average budget above $50 million. Solution: Solution explanation: Select the column language from the table movies. To compute the average budget, use the aggregate function AVG() with the column budget in parentheses. Name the colu.
Database exercises pdf
2015 studio album by Mgła
Exercises in Futility is the third studio album by Polish black metal band Mgła. It was released on 4 September 2015, through Northern Heritage Records. Featuring a raw, melodic black metal style that was compared to those of Watain and early Burzum, the album is regarded as the biggest and most impactful release of the band's 15-year career. The front cover features an artwork from French engraver extiw>Marcel Roux, titled L'aveugle.
