Add task 01 (#50)

task1/Nakhodnov_1_1.sql

@@ -0,0 +1,9 @@
+select
+       cd_customers.customer_rk, (
+           case
+               when cd_customers.middle_nm like '%НА' then 'F'
+               when cd_customers.middle_nm like '%ИЧ' then 'M'
+               end
+           ) as gender
+from srcdt.cd_customers as cd_customers
+where cd_customers.valid_to_dttm = '5999-01-01 00:00:00'

task1/Nakhodnov_1_2.sql

@@ -0,0 +1,5 @@
+select cd_customers.monthly_income_amt
+from srcdt.cd_customers as cd_customers
+where 2014 >= year(cd_customers.valid_from_dttm) and year(cd_customers.valid_to_dttm) >= 2014
+order by cd_customers.monthly_income_amt desc
+limit 10

task1/Nakhodnov_1_3.sql

@@ -0,0 +1,4 @@
+select distinct concat(floor(year(cd_customers.birth_dt) / 10), '0-е') as generation
+from srcdt.cd_customers as cd_customers
+where cd_customers.valid_to_dttm = '5999-01-01 00:00:00'
+order by generation desc