15Apr 2019 by Grant Fritchey 2 Comments

Database Fundamentals #21: Using the JOIN Operator, OUTER JOIN

Database Fundamentals, SQL Server
The OUTER JOIN returns one complete set of data and then the matching values from the other set. The syntax is basically the same as INNER JOIN but you have to include whether or not you’re dealing with a RIGHT or a LEFT JOIN. The OUTER word, just like the INNER key word, is not required. OUTER JOIN Imagine a situation where you have a list of people. Some of those people have financial transactions, but some do not. If you want a query that lists all people in the system, including those with financial transactions, the query might look like this: SELECT p.LastName, ft.TransactionAmount, ft.TransactionDate, ft.TransactionTime FROM Personnel.Person AS p LEFT JOIN Finance.FinancialTransaction AS ft ON p.PersonID = ft.PersonID; Except for the addition of the LEFT key word, this…
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03Dec 2018 by Grant Fritchey 9 Comments

Database Fundamentals #20: Using the JOIN Operator, Inner Join

Database Fundamentals
It is entirely possible to try to JOIN two tables on almost any field, as long as the two data types can, in some way, be made to reconcile to each other, you can try to join the tables. But, most database designs assume a much more directly relationship and provide a column or columns in one table that match the identifying column or columns in the other table. INNER JOIN The INNER JOIN will return the parts of both data sets that match. Frequently, what you'll see when joining two tables is the same column name in each table. With that, you have to be sure to identify the owner of each column. I've introduced what is called an alias to make it so I don't have to type…
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12Jun 2017 by Grant Fritchey 2 Comments

Database Fundamentals #2: SQL Server Management Studio

Database Fundamentals
The best way to learn any software is to start using it. There are a bunch of software tools in the SQL Server toolbox, but the biggest and most important is SQL Server Management Studio (SSMS). SSMS is where you'll spend most of your time when you start to work with SQL Server. It provides a very large series of graphical user interfaces for creating databases, setting up security, reading data out of the database, and all sorts of other things within your SQL Server instances, the databases stored there, and all the stuff inside those databases. It also supplies you with an interface to the basic scripting language of SQL Server, through which you can do almost anything to the server. The scripting language is called Transact Structured Query…
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12Apr 2016 by Grant Fritchey 8 Comments

A View Is Not A Table

Azure, SQL Server, SQL Server 2016, T-SQL
Blog post #4 in support of Tim Ford’s (b|t) #iwanttohelp, #entrylevel In SQL Server, in the T-SQL you use to query it, a view looks just like a table (I'm using the AdventureWorks2014 database for all these examples): SELECT * FROM Production.vProductAndDescription AS vpad;   SELECT vpad.Name, vpad.Description, vpmi.Instructions FROM Production.vProductAndDescription AS vpad JOIN Production.Product AS p ON p.ProductID = vpad.ProductID JOIN Production.vProductModelInstructions AS vpmi ON vpmi.ProductModelID = p.ProductModelID WHERE vpad.ProductID = 891 AND vpad.CultureID = 'fr'; The above query actually combines two views and a table. This is what is commonly referred to as a "code smell". A code smell is a coding practice that works, but that can lead to problems. In this case, we're talking about performance problems. The performance problems when using views to join to…
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