WGU CS1011 Sophia Introduction to Relational Databases Milestone 2 Retake Questions and Answers Score 20/25.
WGU CS1011 Sophia Introduction to Relational Databases Milestone 2 Retake Questions and Answers Score 20/25. 20/25 that's 80% RETAKE 20 questions were answered correctly. 4 questions were answered incorrectly. 1 question was skipped. These were marked incorrect. In each milestone, you may want or need to use the database and query tool to answer some of the questions. We suggest you open the tool in another browser tab while you are working on this assessment. Which of the following is true of foreign keys? ● ● Tables could be created first to avoid having to create foreign keys in order. A foreign key should always be linked to a primary key of another table. ● A foreign key can be linked to any foreign key. UNIT 2 — MILESTONE 2 20/25 CONCEPT → Foreign and Primary Keys 2 RATIONALE In most cases, a foreign key should be linked to a candidate key that is generally a primary key or a unique key. Foreign keys could be temporarily disabled to simplify dropping the tables or moving valid data. Foreign keys could also be added after tables have been created to avoid having to generate them in the right order. Report an issue with this question In each milestone, you may want or need to use the database and query tool to answer some of the questions. We suggest you open the tool in another browser tab while you are working on this assessment. Which of the following is the valid syntax for creating a VIEW to view a subset of a table? ● ● A foreign key is not needed if the data type is different. ● CREATE VIEW album_cost AS track GROUP BY album_id; UNIT 2 — MILESTONE 2 20/25 CONCEPT → VIEW to Provide a Subset 3 RATIONALE Common mistakes include- forgetting the "AS", not doing a select statement, and not including the FROM clause. Report an issue with this question In each milestone, you may want or need to use the database and query tool to answer some of the questions. We suggest you open the tool in another browser tab while you are working on this assessment. ● ● CREATE VIEW album_cost AS SELECT album_id, SUM(unit_price) GROUP BY album_id; ● CREATE VIEW album_cost SELECT album_id, SUM(unit_price) FROM track GROUP BY album_id; CREATE VIEW album_cost AS SELECT album_id, SUM(unit_price) FROM track GROUP BY album_id; UNIT 2 — MILESTONE 2 20/25 Which of the following queries will use a subquery to find all of the rows in the track table that has a unit_price of 0.99 and has the length of the song in milliseconds that is longer than the AVG track length of all tracks in the album_id between 5 and 10? ● SELECT * FROM TRACK WHERE milliseconds > SELECT AVG(milliseconds) FROM track WHERE album_id BETWEEN 5 AND 10 AND unit_price = 0.99; SELECT * FROM TRACK WHERE milliseconds > (SELECT AVG(milliseconds) FROM track WHERE album_id BETWEEN 5 AND 10) AND unit_price = 0.99; ● SELECT AVG(milliseconds) FROM TRACK WHERE milliseconds > (SELECT * FROM track WHERE album_id BETWEEN 5 AND 10) AND unit_price = 0.99; SELECT * FROM TRACK WHERE milliseconds > UNIT 2 — MILESTONE 2 20/25 CONCEPT → Subqueries 4 RATIONALE Common issues include not using ( and ) around the subquery, not having the condition in the right WHERE clause, having more columns being returned in the subquery than in the column comparison list, or not using the aggregate function in the subquery. Report an issue with this question.
Written for
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- WGU CS1011
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- November 6, 2023
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- 2023/2024
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- wgu cs1011 questi
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wgu cs1011 sophia introduction to relational
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introduction to relational databases milestone 2
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wgu cs1011 introduction to relational databases
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wgu cs1011 retake questions and answers
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