how to determine whether an idea should be treated as table or attribute in relational database? -

i'm database beginner , i'm confused regards entity relationship. don't know when should idea classified attribute (i.e. field) or table (i.e. entity). can please me understand this. thank you.

terminology issues can confusing. , it's hard because experts , authors have not been consistent each other since relational model launched in 1970. here's how learned it.

at conceptual level, 1 concerned how values stored , managed database relate subject matter. subject matter analyzed entities , relationships among entities (er model). attributes features of entities or relationships can described data values. database values instances of attributes.

at logical level, 1 concerned relational model of data. relations in relational data model mathematical relations, relational math can presumed hold. attributes discovered @ conceptual level become (named) attributes of relations. relations sets of tuples common attributes. tuples identified keys , referenced elsewhere foreign keys. constraints on data enforce business rules. values stored @ intersection of attribute , tuple.

at physical level, 1 concerned tables made of rows , columns. in addition there database objects such indexes , tablespaces may dbms specific. table representation of relation, rows represent tuples , columns represent attributes. values stored @ intersection of row , column.

sql server documentation tends use terms record , field use terms row , column.

the conceptual level describes requirements without regard implementation. logical level specific relational implementation. physical level specific particular dbms product, oracle or sql server.

in practice, express logical level in sql terminology, such tables, rows, , columns, try keep free dbms dependencies.

i'm afraid description extremely condensed. competent authors can take hundred pages of text flesh out i've said. hope helps.