SQL Server Minus Operator

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The MINUS operator is an Oracle operator and does not exist in SQL Server. SQL Server has its own operator that does this called EXCEPT. The usage of these two operators are the same between Oracle and SQL Server.

 
The EXCEPT Operator
The EXCEPT operator will take two queries and only show the records in the first query that do not exist in the second query. Here is an example of how this would work.

SELECT	A.AnimalName,
		AT.AnimalTypeName
FROM	Animal A
INNER	JOIN AnimalType AT ON AT.AnimalTypeID = A.AnimalTypeID

EXCEPT

SELECT	EA.AnimalName,
		AT.AnimalTypeName
FROM	ExtinctAnimal EA
INNER	JOIN AnimalType AT ON AT.AnimalTypeID = EA.AnimalTypeID

 
The above query will show all the animals from the Animal table where the animals are not in the ExtinctAnimal table.

 
 
Reference: https://msdn.microsoft.com/en-us/library/ms188055.aspx

LIKE in SQL

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The LIKE operator in SQL Server allows you to query data using patterns instead of exact matches. Normal select statements using the = operator will only return records where there is an exact match (usually the casing or trailing spaces do not matter). With the LIKE operator, it does not need to be an exact match.

LIKE
The most basic concept of the like operator is that it allows you to query data without using an exact match in the WHERE clause. It allows you to use some wildcard characters to get the results you are looking for. Here is a basic example:

SELECT	*
FROM	Animal
WHERE	AnimalName LIKE 'Giant %'

[table width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
AnimalID,AnimalName,AnimalType,Animal Weight
35,Giant Squid,Fish,400
36,Giant Panda,Mammal,500
37,Giant Clam,Fish,60
[/table]

The above statement uses the % as a wildcard. It basically says, show me any animals that start with the word Giant. This would return things like Giant Panda, Giant Squid, and Giant Clam.

Although % is the most common wildcard that is used with LIKE, there are many more. Here is a list of all the allowed wildcards.

%
Will allow zero or any characters. You can use this before, after, or in-between any string.

SELECT	*
FROM	Animal
WHERE	AnimalName LIKE 'GIANT %'
	OR AnimalName LIKE '% Penguin'
	OR AnimalName LIKE 'Hammer% Shark'

[table width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
AnimalID,AnimalName,AnimalType,Animal Weight
35,Giant Squid,Fish,400
36,Giant Panda,Mammal,500
37,Giant Clam,Fish,60
38,Emperor Penguin,Bird,15
39,Hammer Head Shark,Fish,90
[/table]

 
_
Will allow any 1 character.

SELECT	*
FROM	Animal
WHERE	AnimalName LIKE 'Chicke_'

[table width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
AnimalID,AnimalName,AnimalType,Animal Weight
18,Chicken,Bird,5
[/table]

 
[]
Will allow 1 character that is specified in the brackets. There are two ways to specify this. [a-d] or [abcd].

The following example will match both goose and moose.

SELECT	*
FROM	Animal
WHERE	AnimalName LIKE '[gm]oose'

[table width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
AnimalID,AnimalName,AnimalType,Animal Weight
11,Goose,Bird,15
27,Moose,Mammal,1000
[/table]

 
The following example will match both cat and bat, but it will NOT match rat.

SELECT	*
FROM	Animal
WHERE	AnimalName LIKE '[a-d]at'

[table width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
AnimalID,AnimalName,AnimalType,Animal Weight
10,Cat,Mammal,10
34,Bat,Bird,1
[/table]

 
[^]
Will match any 1 character that is NOT specified in the brackets. There are two ways to specify this. [^a-d] or [^abcd].

The following example will match horse, but will NOT match zorse… and yes, zorse is an animal… I found it on the internet.

SELECT	*
FROM	Animal
WHERE	AnimalName LIKE '[^z]orse'

[table width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
AnimalID,AnimalName,AnimalType,Animal Weight
6,Horse,Mammal,750
[/table]

 
The following example will match rat, but will NOT match bat or cat.

SELECT	*
FROM	Animal
WHERE	AnimalName LIKE '[^a-d]at'

[table width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
AnimalID,AnimalName,AnimalType,Animal Weight
33,Rat,Mammal,1
[/table]

 
Important
If you are comparing a CHAR data type with the like operator, it may not work correctly. This because when you save data to a CHAR field it will space pad the field to the size of the field. To get around this, you need to trim the spaces from the end of the field.

SELECT	*
FROM	Animal
WHERE	RTRIM(AnimalName) LIKE '%monkey'

 
NOT Like
If you want to match where a pattern is NOT like a string, simply put the word NOT in front of the word LIKE.

SELECT	*
FROM	Animal
WHERE	AnimalName NOT LIKE ‘%monkey’

 
 
Escaping The Wildcard
From time to time you will need to actually search for a pattern containing one of the wildcard characters. Let’s say that you wanted to search for anything in a string that had 10% in it. The % (percent symbol) is a reserved word with the LIKE operator. You would search for the % character by using the ESCAPE clause.

SELECT	*
FROM	Invoice
WHERE	LineItemDescription LIKE '10!%%' ESCAPE '!'

In the query above, you can see that !% in the comparison string means to the literal character %. The ESCAPE clause tells the query to not apply the wildcard rules to any character following the specified characters. In this case, we are specifying the ! (exclamation mark).

[table width=”500″ colwidth=”20|100|50″ colalign=”left|left|center|left|right”]
InvoiceID,ItemName,LineItemDescription
1,Coupon Code,10% off web coupon
[/table]

 
Reference: https://msdn.microsoft.com/en-us/library/ms179859.aspx