Search results
Results From The WOW.Com Content Network
SELECT isbn, title, price FROM Book WHERE price < (SELECT AVG (price) FROM Book) ORDER BY title; A subquery can use values from the outer query, in which case it is known as a correlated subquery . Since 1999 the SQL standard allows WITH clauses for subqueries, i.e. named subqueries, usually called common table expressions (also called subquery ...
So if two tables are T1 and T2, SELECT * FROM T1, T2 will result in every combination of T1 rows with every T2 rows. E.g., if T1 has 3 rows and T2 has 5 rows, then 15 rows will result. Although not in standard, most DBMS allows using a select clause without a table by pretending that an imaginary table with one row is used.
A programmer can use an alias to temporarily assign another name to a table or column for the duration of the current SELECT query. Assigning an alias does not actually rename the column or table. This is often useful when either tables or their columns have very long or complex names. An alias name could be anything, but usually it is kept short.
Patrick T. Fallon/Bloomberg via Getty Images A day at the park has never been more popular. North America's 20 largest amusement and theme parks attracted 138.1 million guests last year -- up 2.2 ...
Here ID serves as the primary key in the table 'Author', but also as AuthorID serves as a Foreign Key in the table 'Book'. The Foreign Key serves as the link, and therefore the connection, between the two related tables in this sample database. In a relational database, a candidate key uniquely identifies each row of data values in a database ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
For example, a prize showing "357" has a price of either $35 or $57. Each time the contestant chooses a correct price, they win that prize and select one key from a rack of five. Three of the keys correspond to one prize lock each, one will open none of the locks, and one (the "Master Key") opens all three.
AOL latest headlines, entertainment, sports, articles for business, health and world news.