Say I have 2 tables: Customers and Orders. A Customer can have many Orders. Now, I need to show any Customers with his latest Order. This means if a Customer has more than one Orders, show only the Order with the latest Entry Time. This is how far I managed on my own: This of course returns all Customers with
Tag: sql
How to restrict NULL as parameter to stored procedure SQL Server?
Is it possible to create a stored procedure as CREATE PROCEDURE Dummy @ID INT NOT NULL AS BEGIN END Why is it not possible to do something like this?
How can I filter out the rows which contain a particular column with null or empty data in SQL?
In SQL, How we make a check to filter all row which contain a column data is null or empty ? For examile Select Name,Age from MEMBERS We need a check Name should not equal to null or empty.
Is there a good reason to use upper case for SQL keywords? [closed]
Closed. This question is opinion-based. It is not currently accepting answers. Want to improve this question? Update the question so it can be answered with facts and citations by editing this post. Closed 6 years ago. Improve this question The default seems to be upper case, but is there really any reason to use upper case for keywords? I started
What is the difference between HAVING and WHERE in SQL?
What is the difference between HAVING and WHERE in an SQL SELECT statement? EDIT: I have marked Steven’s answer as the correct one as it contained the key bit of information on the link: When GROUP BY is not used, HAVING behaves like a WHERE clause The situation I had seen the WHERE in did not have GROUP BY and
How to create relationships in MySQL
In class, we are all ‘studying’ databases, and everyone is using Access. Bored with this, I am trying to do what the rest of the class is doing, but with raw SQL commands with MySQL instead of using Access. I have managed to create databases and tables, but now how do I make a relationship between two tables? If I
Is RIGHT JOIN Ever Required?
Do any queries exist that require RIGHT JOIN, or can they always be re-written with LEFT JOIN? And more specifically, how do you re-write this one without the right join (and I guess implicitly …
Is it possible to execute a text file from SQL query?
I have a number of generated .sql files that I want to run in succession. I’d like to run them from a SQL statement in a query (i.e. Query Analyzer/Server Management Studio). Is it possible to do something like this and if so what is the syntax for doing this? I’m hoping for something like: I am using SQL Server
How do you OR two LIKE statements?
I have tried the following two statements: SELECT col FROM db.tbl WHERE col (LIKE ‘str1’ OR LIKE ‘str2’) AND col2 = num results in a syntax error SELECT col FROM db.tbl WHERE page LIKE (‘str1’ OR ‘…
What should I consider when selecting a data type for my primary key?
When I am creating a new database table, what factors should I take into account for selecting the primary key’s data type?