use sample_first_db; select * from sample_first_db..customers; select * from sample_first_db..[orders]; -- april may month customers order count --step 1 select *, month([order date]) mnth from orders where month([order date]) in (4,5) --step2 select [customer id], mnth, count(distinct [order id]) cnt from (select *, month([order date]) mnth from orders where month([order date]) in (4,5)) a group by [customer id],mnth --step3 select [customer id],MONTH([order date]) as month, COUNT(DISTINCT [order id]) count from orders  where MONTH([order date]) in (4,5) group by [customer id],MONTH([order date]) select [customer id], case when months = 4 then 'April'  When months = 5 then 'May' end as month_name, counts from (select [customer id], MONTH([order date]) as months,  COUNT(DISTINCT [order id]) counts  from orders  where MONTH([order date]) in (4,5)  group by [customer id],MONTH([order date]))inner_table; -- inner table alias name use. use

 drop table if exists table1; create table table1(id VARCHAR(30)); insert into table1 (id) values (1), (2), (3), (4), (5), (null) --insert into table1 values ('hello') --error in joins if in on condition we use this table with other interger value table -- not error if we use only table 2 interger value with integer. table.id = 2;  --like tihs select * from table2 left join table1 on table2.id = 2; select * from table1; drop table if exists table2; create table table2 (id integer); insert into table2 (id) values (2), (2), (6), (4); --insert into table2 (id) values ("hello"); select * from table2; select * from table1; select * from table2; --inner join select * from table1 inner join table2 on table1.id = table2.id; select * from table1,table2 where table1.id = table2.id; select * from table1 cross join table2 where table1.id = table2.id; -- error if we use "on" in crossjoin. use where clause with crossjoin. --iner join on = cross join where = same result se

There are many misconceptions related to the data analyst job profiles. That you need to learn hardcore programming, maths, and machine learning algorithm to get a data analyst job in 2023. Some people also mix these 3 filed quite frequently. Data Analysis, Data Science, and Data Engineering. Skills to become data analysts in 2023 Excel SQL Tableau/Power-Bi. That's it. And if you have the below skills that would be an advantage. Python Statistics