当前我国的计算机应用已经深入到社会的各个领域，越来越多的单位建立了以数据库为核心的管理信息系统。关系型数据库系统以其理论基础严格、语言简洁、易学易用、高度非过程化等特点在市场上占据优势。目前流行的大多数数据库系统都是关系型数据库 ...

回答： 有一个方法可以返回一个近似值，只需要在where后加上：AND rowid=(trunc(rowid/x)*x) 其中的x代表你想要返回的总的记录的1/x ...

如果你有排序和连接操作，你可以先select数据到一个临时表中，然后再对临时表进行处理。因为临时表是建立在内存中，所以比建立在磁盘上表操作要快的多。 如： SELECT time_records.*, case_name FROM time_records, OUTER cases WHERE time_records.client = "AA1000" AND time_records.case ...

Does anyone know how, once terminal'd into a Unix box (I know very little about navigating Unix), I can execute a sql statement against the informix database installed on the system?<BR><BR>SQL Server ...

To connect to an Informix-SE database, you must either be in the directory that contains the database or you must specify the full pathname of the database in the DATABASE= argument. The following ...

specifies a dynamic, DBMS-specific SQL statement that does not select data. This argument is required and must be enclosed in parentheses. The statement is case sensitive and is passed to the DBMS ...