我正在研究适当的关系图书馆,从克里斯托弗日刊. 在整个书中,他使用了他和Hugh Darwen的语言,以传达理论——。 总的来说,我认为Tutorial D是一种非常可操作的问答语,比LQ更灵活,因此,我(Frank for fun)热衷于在书面上打一个表格(穷人,无疑是做不到)根据Tutorial D而不是D建造的RDBMS。
实现这一点,是一项甚至只是要作一些基本内容的任务,我想知道,现有储存系统是否不代表KQ意义上的表格,而是代表关系关系,不使用任何特定的询问语言来获取数据,而只是提供低级功能,如<条码><产品/编码>、<条码>>/编码>、<条码>、<>条令/编码>、<条码>、<>条码>>、<>条码>、<>条码>、<>>项目等(在C级,而不是在查询语言一级)。
我是否有意义? 基本上,我喜欢做这样的事,并贴上Tutorial D(或类似)的问答。
记忆中一切都非常容易,但以哪一种方式代表软磁盘上的数据结构,这种方式甚至效率极低,而且可能过于我的头部,没有认真研究。
http://en.wikipedia.org/wiki/Query_optimizer”rel=“nofollow” Query Bestizer , 查询和生成一套Execution Plans。
然后在数据库上执行最优化的执行计划;该计划产生的结果。
So, if you took an open source RDBMS implementation and wanted to modify it to accept a different query language, all you would have to do would be to translate the query language of your choice into an execution plan.
That s not to say that what you re trying to do is easy. Just that it should be possible, without having to write your own RDBMS. You would need to write a lexer and interpreter for your query language and then figure out how to transfer your interpreted query expression to the database engine s optimizer so that it can generate the execution plans, and execute the most efficient of them.
http://www.sqlite.org”rel=“nofollow”
Dave Voorhis 你似乎想要建设的东西已经存在。
rel=“nofollow” http://dbappbuilder.sourceforge.net/Rel.php
不管怎样,你有明确的目的,为......做尝试和建设。
$db_user="root"; $db_host="localhost"; $db_password="root"; $db_name = "fayer"; $conn = mysqli_connect($db_host,$db_user,$db_password,$db_name) or die ("couldn t connect to server"); // perform query ...
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