Mysql – SQL READING THE COLUMN VALUES?
0.0.0.1 saved in sql table column as 10001. MY data base contains values as such above mentioned i wanted to sort it based on the values but if I sort is as it is it will give me wrong order…
Mysql – Get all distinct values from column1 in case of 2 similar rows, get the one with column2 not null
I have a large table as dataset. If there are 2 similar rows with same date and id then how do I get the row for which another column value is not null? SELECT *, row_number() over (partition by id…
Mysql – How does these 2 sql queries work – to find two minimum and maximum salaries
Can anyone explain how does this two queries work ? Q) Write a query to retrieve two minimum and maximum salaries from the EmployeePosition table. To retrieve two minimum salaries, you can write a query as below: A)To retrieve two…
Is there a way to find max values of three column in mysql
I have been working on a project which analyze credit rate from different bank. I have a simple table structured like below `id` varchar(255) DEFAULT NULL, `credit_name` varchar(255) DEFAULT NULL, `credit_name2` varchar(255) DEFAULT NULL, `rate_home` float DEFAULT NULL, `rate_vehicle` float…
Mysql – Select name, lastname, brand from table where brand is the most voted
I have this select SELECT firstname, lastname, email, brand FROM (SELECT brand, COUNT(brand) AS choiced FROM users GROUP BY brand ORDER BY `choiced` DESC LIMIT 1) AS winner ORDER BY RAND() LIMIT 1 Error #1054 column firstname in field set…
Mysql – Execution time taken by different SQL JOINS
Below two queries result the same result set. In first I have only used INNER JOIN and in second query mix of joins like LEFT and RIGHT JOIN. I personally prefer INNER JOIN when there is no specific task/requirement of…
Postgresql – Making rank() ignore null cases
I'm trying to figure out a way to make the rank() window function "skip" in its counting some rows with null values in a specific column. Pretty much, what I want is to count how many paid transactions there are,…
Mysql – how to sovle ambiguous column name: nation.n_nationkey in sql?
how do I solve the problem "ambiguous column name: n_name" and separate supplier and customer's nation? SELECT count(l_orderkey) FROM lineitem INNER JOIN orders ON lineitem.l_orderkey = orders.o_orderkey INNER JOIN customer ON orders.o_custkey = customer.c_custkey INNER JOIN nation ON customer.c_nationkey =…
Mysql – SQL: How to join two tables and extract the data by timestamp?
I'm using mysql. I have two tables, one is about movie type, and the other is about movie rating with timestamps. I want to join these two tables together with movie id to count the average rating for each type…
Postgresql – SQL query returns nothing when looking for records that are not in another table
I have created two tables and populated them: CREATE TABLE FirstTab ( id integer, name VARCHAR(10) ); INSERT INTO FirstTab VALUES (5,'Pawan'), (6,'Sharlee'), (7,'Krish'), (NULL,'Avtaar'); CREATE TABLE SecondTab ( id integer ); INSERT INTO SecondTab VALUES (5), (NULL); I am…