To select specific rows, you can use the WHERE clause. In WHERE clauses, you can specify search conditions. Some of these conditions are presented below.
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SQL Reference Manual, Predicate (predicate)
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SELECT title, name
FROM hotel.customer
WHERE title ='Company'
Selecting the customers that are companies
Result
TITLE |
NAME |
Company |
Datasoft |
Company |
TOOLware |
SELECT firstname, name, zip
FROM hotel.customer
WHERE name > 'Randolph'
Selecting the customers that, in alphabetical order, come after Randolph
Result
FIRSTNAME |
NAME |
ZIP |
Sally |
Smith |
75243 |
? |
TOOLware |
20019 |
See also: SQL Reference Manual, Comparison Predicate (comparison_predicate)
If AND and OR are both used, make sure that AND has a higher priority than OR. You should use parentheses to illustrate the desired multiple conditions. You can also use multiple parentheses. The system then evaluates the data from the innermost to the outermost parentheses.
SELECT firstname, name, zip
FROM hotel.customer
WHERE (title ='Company') AND (name > 'Randolph')
Selecting the customers that, in alphabetical order, come after Randolph and that are companies
Result
FIRSTNAME |
NAME |
ZIP |
? |
TOOLware |
20019 |
See also: SQL Reference Manual, Search Condition (search_condition)
SELECT title, name, zip
FROM hotel.customer
WHERE zip BETWEEN '10000' AND '30000'
Selection of customers who live in towns with a post code between 10000 and 30000.
Result
TITLE |
NAME |
ZIP |
Mrs |
Porter |
10580 |
Mrs |
Griffith |
20005 |
Company |
TOOLware |
20019 |
Mr |
Jenkins |
20903 |
See also: SQL Reference Manual, BETWEEN Predicate (between_predicate)
You can specify the values in the parentheses in any order you desire, since this is a set of values from which a value is to be selected using the IN predicate.
SELECT title, firstname, name
FROM hotel.customer
WHERE title IN ('Mr','Mrs')
Selecting all customers who are natural persons (not companies)
Result
TITLE |
FIRSTNAME |
NAME |
Mrs |
Jenny |
Porter |
Mr |
Peter |
Brown |
Mrs |
Rose |
Brian |
Mrs |
Mary |
Griffith |
Mr |
Martin |
Randolph |
Mrs |
Sally |
Smith |
Mr |
Mike |
Jackson |
Mrs |
Rita |
Doe |
Mr |
George |
Howe |
Mr |
Frank |
Miller |
Mrs |
Susan |
Baker |
Mr |
Joseph |
Peters |
Mr |
Antony |
Jenkins |
See also: SQL Reference Manual, IN Predicate (in_predicate)
More examples for Data Query