Differences
EJB QL is a database query language similar to SQL. The used queries are somewhat different from relational SQL, as it uses a so-called "abstract schema" of the enterprise beans instead of the relational model. In other words, EJB QL queries do not use tables and their components, but enterprise beans, their persistent state, and their relationships. The result of an SQL query is a set of rows with a fixed number of columns. The result of an EJB QL query is either a single object, a collection of entity objects of a given type, or a collection of values retrieved from CMP fields. One has to understand the data model of enterprise beans in order to write effective queries.
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Famous quotes containing the word differences:
“The extent to which a parent is able to see a child’s world through that child’s eyes depends very much on the parent’s ability to appreciate the differences between herself and her child and to respect those differences. Your own children need you to accept them for who they are, not who you would like them to be.”
—Lawrence Balter (20th century)
“Toddlerhood resembles adolescence because of the rapidity of physical growth and because of the impulse to break loose of parental boundaries. At both ages, the struggle for independence exists hand in hand with the often hidden wish to be contained and protected while striving to move forward in the world. How parents and toddlers negotiate their differences sets the stage for their ability to remain partners during childhood and through the rebellions of the teenage years.”
—Alicia F. Lieberman (20th century)