The Language of SQL- P48 doc
The Language of SQL- P48 doc
... or save the file, select the RUN button.
The setup wizard will then start.
10. On the Welcome screen, click the NEXT button.
11. On the Setup Type screen, select COMPLETE and then click the NEXT
button.
12. ... in the Name textbox. Click the APPLY button twice and then
the FINISH button. You will now see your new database in the Object Explorer.
Finally, using the Defa...
The Language of SQL- P10 doc
... result:
The Answer
the apple
The LTRIM function enables you to get rid of the spaces to the left of ‘ the apple.’’
Note that
LTRIM is smart enough not to eliminate spaces in the middle of a
phrase. ... spaces, either on the
left or on the right side of a value. The
LTRIM function ‘‘trims’’ characters from
the left side of a character. For example:
SELECT
LTRIM (...
The Language of SQL- P11 docx
... ‘7/2/2009’) 5
Looking at the values in the above chart, you can see that the month of 7/2/2009
is 7. The day is 2. The week is 27, because 7/2/2009 is in the 27th week of the year.
The weekday is 5 because ... elements as the day or week of the date. Again, the name
of this function differs, depending on the database . In Microsoft SQL Server, this
function is...
The Language of SQL- P14 docx
... covered some of the quirks of
sorting, particularly when it comes to data with NULL values and with numbers
in character columns.
At the start of the chapter, we mentioned some of the general ... Sequences
In the previous examples, all of the data is character data, consisting of letters
from A to Z. There are no numbers or special characters. Additionally, there has
b...
The Language of SQL- P16 docx
... order to apply the needed logic. The simple format only works with an analysis
of a single column.
Due to the inherent complexity of IF-THEN-ELSE logic, the
CASE expression is one
ofthemorechallengingtopicsinthisbook.Inthischapter,wehavefocusedon
using
CASE ... task of selecting a subset of rows. The logic utilized for the
WHERE keyword builds on the column-based logic s...
The Language of SQL- P23 docx
... rows that are selected, and then it returns a count of the number
of rows.
In the second format of the
COUNT function, a specific column is specified rather
than the asterisk. Here’s an example:
SELECT
COUNT ... statements. In the
first, you’re merely counting rows where the GradeType equals ‘‘Homework.’’
There are three of these rows. In the second, you’re counting occu...
The Language of SQL- P29 doc
... the primary table, even if there is no match in the secondary
table. The right join is simply the reverse of the left join, switching the order of
the primary and secondary tables. Finally, the ... creates a virtual
view of the table, in the sense that we can now view this table from two different
perspectives. The second main topic of the next chapter will ext...
The Language of SQL- P30 docx
... view of the Personnel table and the
EmployeeID column of the Managers view of the table. In other words, the
indicated manager is also an employee.
Notice that Susan Ford isn’t shown in the previous ... Bland
The trickiest part of this SELECT is the ON clause in the join. To get the self join
to work correctly, we need to use the
ON to establish a relationship be...
The Language of SQL- P31 docx
... create a view of the table for
those users. You can then use the security features of your database to grant
access to the new view for those users, while restricting them from accessing
the underlying ... Orders.OrderID ¼ Refunds.OrderID
The only item missing in the above CREATE VIEW is the ORDER BY clause of the
original
SELECT statement. Since views aren’t stored as p...
The Language of SQL- P34 docx
... to retrieve data.
The concept of combining queries is often referred to as set logic , a term taken
from mathematics. Each
SELECT query can be referred to as a set of data. The set
logic we will ... the
SELECT columnlist. In other words, after the
subquery is evaluated, it returns a single value, which is then included in the
columnlist. Here’s a general format of the above...
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