October 2002
Beginner
864 pages
18h 41m
English
Content preview from Sams Teach Yourself SQL in 21 Days, Fourth Edition
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Day 10
Quiz
| 1: | Is there a limit to the number of columns in a table that can be defined as unique? |
| A1: | There is no limit to the number of unique constraints that you can have in a table. |
| 2: | What does a check constraint do? |
| A2: | A check constraint checks to see whether inserted data in a column meets certain criteria, as specified in the definition of the check constraint. |
| 3: | When inserting data into the database, which record must be inserted first, the parent or the child? |
| A3: | The parent record must always be inserted first. |
| 4: | When deleting data from the database, which record must be deleted first, the parent or the child? |
| A4: | The child record must always be deleted first. |
Exercises
| 1: | You created the CUST, STOCK, and MEDIA tables today. Perform the ... |
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