Chapter 2 Flashcards
SQL includes a data definition language, a data manipulation language, and SQL/Persistent stored modules
True
SQL stands for Standard Query Language
False
SQL is only a data manipulation language (DML)
False
The American National Standards Institute (ANSI) maintains the standards for SQL
True
SQL was developed by IBM in the late 70s
True
SQL is not a complete programming language. Rather it is a data sub language.
True
In addition to being a data sub language, SQL is also a programming language, like java or C#
False
SQL commands can be embedded in application programs
True
SQL although very popular has never become a national standard
False
The SQL keyword SELECT is used to specify the columns to be listed in the query results
True
The SQL keyword WHERE is used to specify the tables that contain(s) the data to be retrieved
False
The SQL keyword FROM is used to specify the table to be used
True
SQL can only query a single table
False
SQL statements end with a colon
False
The columns to be obtained by an SQL command are listed after the FROM keyword
False
To remove duplicate rows from the result of a query, specify the SQL DISTINCT keyword
True
To obtain all columns, use an asterisk (*) wild card character instead of listing all the column names
True
The SQL WHERE clause contains the condition that specifies which rows are to be selected
True
The result of an SQL SELECT operation can contain duplicate rows
True
To have SQL automatically eliminate duplicate rows from a result, use the keyword DISTINCT with the FROM keyword
False
An asterisk (*) following the SELECT verb means that all columns are to be displayed
True
The WHERE clause contains the condition that specifies which columns are to be selected
False
SQL is a
Data sub language, product of IBM, national standard, combination that includes a data definition language and a data manipulation language
When making an SQL query, we are using SQL as a(n)
DML
In an SQL query, which SQL keyword actually creates the query
SELECT
In an SQL query, which SQL keyword is used to specify the table(s) to be used?
FROM
In an SQL query, which SQL keyword must be used to remove duplicate rows from the result table?
DISTINCT
In an SQL query, which of the follows symbols is used by ANSI SQL to represent all the columns in a single table?
- (asterisk)
The rows of the result table can be sorted by the values in one or more columns
true
sorting is specified by the use of the SORT BY phrase
False
To sort the rows of the result table, the ORDER BY clause is specified
False
Columns can be sorted in descending sequence by using the SQL DESC keyword
True
A WHERE clause can contain only one condition
False
When two conditions must both be true for the rows to be selected, the conditions are separated by the SQL AND keyword
True
To exclude one or more values using a condition, the SQL OUT keyword must be used
False
To refer to a set of values in a condition, the values are placed inside parentheses ( ) and separated by columns
True
The condition in WHERE clauses can refer to a set of values by using the IN operator
True
The SQL keyword LIKE is used in SQL expression to select on partial values
True
The SQL wildcard character “%” represents a series of one or more unspecified characters
True
The SQL wildcard character “#” indicates a single, unspecified character in a specific location in a SQL query
False
The Microsoft Access wildcard character “*” indicated a sequence of one or more unspecified characters in a Microsoft Access SQL query
True
The Microsoft Access wildcard character “_” indicated a single, unspecified character in a specific location in a Microsoft Access SQL query
False
In an SQL query, which SQL keyword is used to join two conditions that both must be true for the rows to be selected?
AND
In an SQL query, which SQL keyword is used to determine if a column value is equal to any one of a set of values
IN
In an SQL query, which of the following symbols is used by ANSI SQL to represents a single unspecified character?
_ (underscore)
In an SQL query, which of the following symbols is used by Microsoft Access to represent a single unspecified character?
? (question mark)
In an SQL query, which SQL keyword is used to sort the result table by the values in one or more columns?
ORDER BY
Given a table with the structure: EMPLOYEE (EmpNo, Name, Salary, HireDate), which of the following would find all employees whose name begins with the letter “S” using standard SQL?
SELECT*
FROM EMPLOYEE
WHERE Name LIKE ‘S%’;
Given a table with the structure: EMPLOYEE (EmpNo, Name, Salary, HireDate), which of the following would find all employees whose name begins with the letter “S” using Microsoft Access?
SELECT *
FROM Name
WHERE EMPLOYEE LIKE ‘S*’;
The SQL keyword GROUP BY instructs the DBMS to group together those rows that have the same value in a column.
True
A WHERE clause can contain another SELECT statement enclosed in parentheses.
True
A SELECT statement used in a WHERE clause is called a subquery.
True
A nested SELECT statement (one that appears within the WHERE clause of another SQL statement) is called a subquery and must be enclosed in parentheses.
True
Only two tables can be queried by using a subquery.
False
An alternative to combining tables by a subquery is to use a join.
True
When people use the term “join” they normally mean an “equijoin.”
True
Two or more tables are joined by giving the table names in the WHERE clause and specifying the equality of the respective column names as a condition in the GROUP BY caluse.
False
The names of the tables to be joined in an SQL query are listed in the FROM clause.
True
In an SQL query, a join operation is achieved by specifying the equality of the respective column names as a condition in the WHERE clause.
True
Every subquery can be alternatively expressed by a join.
False
While many subqueries can be alternatively written as joins, correlated subqueries do work that cannot be duplicated as a join.
True
The SQL syntax JOIN…ON can be used as alternate way of writing an SQL join statement.
True
Joins that show only matching rows from the joined tables in their results are called inner joins.
True
Joins that show the matching rows from the joined tables plus unmatched rows from one other table in their results are called out joints.
True
Outer joins can be either up joins or down joins.
False
In an SQL query, which built-in function is used to total numeric columns?
SUM
In an SQL query, which built-in function is used to compute the average value of numeric columns?
AVG
In an SQL query, which built-in function is used to obtain the largest value of numeric columns?
MAX
In an SQL query, which built-in function is used to obtain the smallest value of numeric columns?
MIN
In an SQL query, the built-in functions SUM and AVG work with columns containing data of which of the following data types?
Integer and Numeric
In an SQL query, which built-in function is used to compute the number of rows in a table?
COUNT
In an SQL query, the built-in function COUNT works with columns containing data of which of the following data types?
Integer, Numeric, Char
In an SQL query, which SQL keyword is used with built-in functions to group together rows that have the same value in a specified column?
GROUP BY
In an SQL query, which SQL keyword is used with GROUP BY to select groups meeting specified criteria?
HAVING
In an SQL query, which SQL keyword is used to implement a subquery?
SELECT
When one SQL query is embedded in another SQL query, this is referred to as a _____ .
subquery
When one SQL query is embedded in another SQL query, the second SQL query is embedded in the ____ of the first query.
WHERE
When one SQL query is embedded in another SQL query, the first SQ query can still contain an SQL _____ clause.
ORDER BY and GROUP BY
In an SQL query, which SQL keyword is used to specify the names of tables to be joined?
FROM
In an SQL query, which SQL keyword is used to specify the column names to be used in a join?
WHERE
Regarding the interchangeability of subqueries and joins,
a join can sometimes be used as an alternative to a subquery, and a subquery can sometimes be used as an alternative to a join (B)
In an SQL query of two tables, which SQL keyword indicated that we want data from all the rows of one table to be included in the result, even if the row does not correspond to any data in the other table?
LEFT JOIN and RIGHT JOIN
