Here are the eight most populous countries in the world:
| Id | Name | Area | Population | Source |
|---|---|---|---|---|
| 18 | India | 3,287,240 | 1,348,834,400 | Based on 2011 census |
| 27 | Bangladesh | 143,998 | 166,774,136 | — |
| 34 | Pakistan | 803,940 | 205,095,217 | Official population clock |
| 42 | Nigeria | 923,768 | 200,962,000 | UN projection |
| 46 | United States | 9,833,517 | 329,424,894 | Official population clock |
| 54 | Brazil | 8,515,767 | 210,076,263 | — |
| 59 | China | 9,640,821 | 1,397,906,480 | Official estimate |
| 60 | Indonesia | 1,904,569 | 268,074,600 | Official annual projection |
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Using your favorite DB client, design and create a database table called
countriesthat would store the information presented above (create a database first if you don’t have any existing ones to play with). Don’t bother with creating any keys or indices for now, just create the five columns. Copy and paste the SQL query generated by the client below (it should start withcreate tableor something similar; if it is difficult to find the query generated by your client, ask for assistance):CREATE TABLE ... -
Manually create a query or a series of queries that would fill the table with the information above. Put the query/queries below:
... here goes your SQL ... -
Create a query that would return everything from the table:
... here goes your SQL ... -
Create a query that would return a single row: the country with the ID of 46.
... here goes your SQL ... -
Create a query that would return the four countries with the following IDs: 18, 34, 54, 59.
... here goes your SQL ... -
Create a query that would return all the countries except the country with the ID of 27 (
Bangladesh).... here goes your SQL ... -
Create a query that would select the names and sources for the countries whose area is over 1,000,000 km2:
... here goes your SQL ... -
Create a query that would select the IDs of the countries with missing sources:
... here goes your SQL ... -
Create a query that would return the area, population, and population density (a computed column aliased
density) of every country that has a source.... here goes your SQL ... -
Create a query that would return the list of all sources, without repetition:
... here goes your SQL ... -
Create a query that would select the countries whose source is official (starting with
Official) or the area is below 1,000,000 km2:... here goes your SQL ... -
Create a query that would select the countries whose source is official (starting with
Official) and the area is below 1,000,000 km2:... here goes your SQL ... -
Create a query that would select all the countries except those whose source is official (starting with
Official):... here goes your SQL ... -
Create a query that would select the countries whose names start with an
N,O,P, ...,X,Y, orZ:... here goes your SQL ... -
Create a query that would return all the countries sorted by their name alphabetically:
... here goes your SQL ... -
Create a query that would return the population density figures of the countries sorted in the descending order. The column should be aliased
density.... here goes your SQL ... -
Create a query that would return the countries sorted by their source alphabetically, and then (if two or more countries share the same source) by their name in the reverse alphabetical order:
... here goes your SQL ... -
Set all sources to
NULL:... here goes your SQL ... -
Update the sources for the countries with the population over 1,000,000,000 to
Official:... here goes your SQL ... -
Multiply the area by 100 and add 10 to the population for every country whose ID is greater than 50:
... here goes your SQL ... -
Delete from the table every country whose population is less than 300,000,000:
... here goes your SQL ... -
Delete all countries from the table:
... here goes your SQL ...
Don’t forget to create a pull request.
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