Manage data with Transact-SQL

Question 1

The main language used to manage and manipulate data in Microsoft SQL Server and Azure SQL Database

Answer 1

Transact-SQL

Question 2

T-SQL has strong foundations in _.

Answer 2

mathematics

Question 3

T-SQL is a dialect of _.

Answer 3

standard SQL

Question 4

SQL is a standard of both the _ and the _.

Answer 4

International Organization for Standards (ISO),

American National Standards Institute (ANSI)

Question 5

Writing SQL in a _ way is considered a best practice.

Answer 5

standard, standardized

Question 6

T/F: T-SQL enforces semicolons for all statements?

Answer 6

False, but is it considered a deprecated feature

Question 7

Standard SQL is based on _, a mathematical model for data management and manipulation.

Answer 7

relational model

Question 8

A mathematical model for data management and manipulation.

Answer 8

relational model

Question 9

T/F: The name “relational” has to do with relationships between tables.

Answer 9

False, it has to do with mathematical concept RELATION.

Question 10

A relation in the relational model is what SQL tries to represent with a _.

Answer 10

table

Question 11

In mathematical terms, a relation has a _ and a _.

Answer 11

heading,

body

Question 12

_ and _ are the relational model’s core foundations for which T-SQL uses for some of it’s most important aspects.

Answer 12

set theory,

predicate logic

Question 13

In the relational model, a _ is a set of attributes, which SQL attempts to represent with _.

Answer 13

heading,

columns

Question 14

In the relational model, a _ is a set of tuples, what SQL attempts to to represent with _.

Answer 14

body,

rows

Question 15

A set should be considered as a _, instead of interacting with the individual elements of the set.

Answer 15

whole

Question 16

T/F: There is no relevance to the order of a set.

Answer 16

True

Question 17

T/F: There is no relevance to the order of a sequence.

Answer 17

False, a sequence is ordered

Question 18

T/F: A set has no duplicates.

Answer 18

True

Question 19

A _ is an expression that when attributed to some object, make a proposition either _ or _.

Answer 19

predicate,
true,
false

Question 20

T-SQL is based more on _ than on set theory.

Answer 20

multiset theory

Question 21

A multiset in many respects is similar to a set, but can have _.

Answer 21

duplicates

Question 22

SQL gives you the _ clause to remove duplicates.

Answer 22

DISTINCT

Question 23

If you need to guarantee a specific presentation order to the rows in the result, you need to add an _ clause to the query.

Answer 23

ORDER BY

Question 24

T/F: When adding an ORDER BY clause, the result is still relational.

Answer 24

False, it’s not relational because it’s ordered.

Question 25

T/F: When you issue a query with SELECT *, you are guaranteed to get the columns in the result based on definition order.

Answer 25

True

Question 26

T-SQL allows referring to _ positions of columns from the result in the ORDER BY clause.

Answer 26

ordinal

Question 27

According to the relational model, all attributes must have _.

Answer 27

names

Question 28

T/F:With T-SQL, a query can return multiple result columns in the same name.

Answer 28

true

Question 29

For the result to be relational, all attributes must have unique _.

Answer 29

names

Question 30

You need to carefully understand what happens when _ are involved in the data you’re manipulating with various query constructs like filtering, sorting, grouping , joining, or intersecting.

Answer 30

NULLs

Question 31

Fields and records are _.

Answer 31

physical

Question 32

A _ is a marker for a missing value, not a value itself.

Answer 32

NULL

Question 33

T-SQL has both _ and _ sides to it.

Answer 33

logical,

physical

Question 34

The main statement used to retrieve data in t-SQL is the _ statement.

Answer 34

SELECT

Question 35

The logical query processing order of the six main query clauses:

Answer 35

1. FROM
2. WHERE
3. GROUP BY
4. HAVING
5. SELECT
6. ORDER BY

Question 36

If a _ clause is specified, it isn’t relational. This means that you can’t operate on such a result with an outer query because an outer query expects a relation as input.

Answer 36

ORDER BY

Question 37

An outer query expects a _ as input.

Answer 37

relation

Question 38

All expressions processed after the _ must guarantee a single value per group.

Answer 38

GROUP BY clause

Question 39

A predicate can evaluate to true, false, or __.

Answer 39

unknown

Question 40

The __ clause is evaluated after the data has been grouped

Answer 40

HAVING

Question 41

The __ clause is evaluated before rows are grouped.

Answer 41

WHERE

Question 42

The __ clause is evaluated per row.

Answer 42

WHERE

Question 43

The __ clause is evaluated per group.

Answer 43

HAVING

Question 44

The query phases in order as you type them are:

Answer 44

1. SELECT
2. FROM
3. WHERE
4. GROUP BY
5. HAVING
6. ORDER BY

Question 45

The SELECT phase returns a __ result.

Answer 45

relational

Question 46

The DISTINCT gets applied during the __ phase.

Answer 46

SELECT

Question 47

Column alias are created during the __ phase.

Answer 47

SELECT

Question 48

__ are not visible to clauses processed in previous phases like FROM, WHERE, GROUP BY, and HAVING.

Answer 48

Column aliases

Question 49

An __ created by the SELECT phase isn’t even visible to the expressions that appear in the same SELECT list.

Answer 49

alias

Question 50

The __ clause is the first and only clause that is allowed to refer to column aliases defined in the SELECT clause.

Answer 50

ORDER BY