finished q1 and started q2

Author: AlexanderConnelly

alexander_connelly_code_challenge.txt

@@ -4,6 +4,92 @@ Data Integrity Checking & Cleanup
 
 - For all countries that have multiple rows in the continent_map table, delete all multiple records leaving only the 1 record per country. The record that you keep should be the first one when sorted by the continent_code alphabetically ascending. Provide the query/ies and explanation of step(s) that you follow to delete these records.
 
+CREATE DATABASE BrainTreeSQLCodingChallenge
+
+CREATE TABLE continent_map (
+    ID int IDENTITY (1 , 1) PRIMARY KEY ,
+    country_code nvarchar(3),
+    continent_code nvarchar(2)
+);
+CREATE TABLE continents (
+    continent_code nvarchar(2),
+    continent_name nvarchar(50)
+);
+CREATE TABLE countries (
+    country_code nvarchar(3),
+    country_name nvarchar(100)
+);
+CREATE TABLE per_capita (
+    country_code nvarchar(3),
+    year int,
+    gdp_per_capita float
+);
+
+# Used Flat File Import to Get CSV files into DB Tables
+
+
+SELECT COALESCE([country_code],'FOO')
+      
+  FROM [dbo].[continent_map]
+
+  group by country_code
+
+  having COUNT(*) > 1
+
+  order by country_code;
+
+Results from first part of question selecting duplicates and brining NULL up top.
+
+country_code:
+FOO
+ARM
+AZE
+CYP
+GEO
+KAZ
+RUS
+TUR
+UMI
+
+Part 2:
+
+/* Create a temporary table with a new column ID as a row_number on the table after order by contry_code, continent_code*/
+ SELECT row_number() over (order by country_code, continent_code asc) as 'ID',[country_code]
+      ,[continent_code] into temp_table
+  FROM [dbo].[continent_map] ;
+  
+/*Delete the rows that dont have a min ID number after group by country_code*/
+  Delete From temp_table where ID NOT IN (Select MIN(ID) from temp_table group by country_code);
+  
+/*Reset continent_map table*/
+Delete From continent_map;
+
+/*Refill continent_map from temp_table*/
+insert into continent_map
+  select country_code, continent_code from temp_table;
+ 
+ /*drop temp_table*/
+ DROP TABLE temp_table
+
+Results in Table continent_map:
+
+country_code	continent_code
+NULL	AS
+ABW	NA
+AFG	AS
+AGO	AF
+AIA	NA
+ALA	EU
+ALB	EU
+AND	EU
+ANT	NA
+ARE	AS
+ARG	SA
+ARM	AF
+ASM	OC
+....... etc 
+
+
 2\. List the countries ranked 10-12 in each continent by the percent of year-over-year growth descending from 2011 to 2012.
 
 The percent of growth should be calculated as: ((2012 gdp - 2011 gdp) / 2011 gdp)
@@ -16,6 +102,27 @@ The list should include the columns:
 - country_name
 - growth_percent
 
+/* in order to do this one I first created a VIEW in my data base which joined the per_capita table to all other tables appropriately. the join looks like this*/
+
+SELECT        dbo.per_capita.country_code, dbo.continents.continent_code, dbo.continents.continent_name, dbo.countries.country_name, dbo.per_capita.year, dbo.per_capita.gdp_per_capita
+FROM            dbo.continent_map INNER JOIN
+                         dbo.countries ON dbo.continent_map.country_code = dbo.countries.country_code INNER JOIN
+                         dbo.continents ON dbo.continent_map.continent_code = dbo.continents.continent_code INNER JOIN
+                         dbo.per_capita ON dbo.continent_map.country_code = dbo.per_capita.country_code
+                         
+/* results from the select look like this:*/
+country_code	continent_code	continent_name	country_name	year	gdp_per_capita
+ABW	NA	North America	Aruba	2004	22566.68216
+AND	EU	Europe	Andorra	2004	29372.16674
+AFG	AS	Asia	Afghanistan	2004	220.0562878
+AGO	AF	Africa	Angola	2004	1229.342988
+..... and on and on
+
+/*Using this view as my dataset to refer to, I'll answer the GDP question with this query:*/
+
+
+
+
 3\. For the year 2012, create a 3 column, 1 row report showing the percent share of gdp_per_capita for the following regions:
 
 (i) Asia, (ii) Europe, (iii) the Rest of the World. Your result should look something like