a DBMS has to go through all the records in the table in order to retrieve the desired results. This process is called table-scanning and is extremely slow. On the other hand, if you create indexes, the database goes to that index first and then retrieves the corresponding table records...
One of the most important features that makes DBMS a better choice over a traditional file system is fast retrieval of data, which is facilitated by indexes. In a relational database every table can have at most one clustered index and many non-clustered index. Though it facilitates fast ...
Congratulations wOOdy-Soft on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go! Home Forums Software Programmers DBMS Packages Sybase: Adaptive (SQL) Server Non clustered index query Thread starter marcmcconnell Start date Oct 9, 2006...
Techopedia Explains Clustered Index In other words, a clustered index stores the actual data, where a non-clustered index is a pointer to the data. In most DBMSs, you can only have one clustered index per table, though there are systems that support multiple clusters (DB2 being an example)...
"String or binary data would be truncated" and field specifications “Unable to enlist in the transaction” with Oracle linked server from MS SQL Server [<Name of Missing Index, sysname,>] in non clustered index [Execute SQL Task] Error: The value type (__ComObject) can only be converte...
To any young/inexperienced DBA's or indeed anyone that may stumble across this post, this is why we do not base our opinions on rare personal experiences caused by bugs in (at time of OP) 11 year old software. Stay up to date with the DBMS that you use and base all your de...
Don't forget that SQL Server imposes the limit that a given table can only have one clustered index, but this limitation does not exist in all DBMSs. So when you answer the question, make sure you and the interviewer are thinking about the same DBMS. ...
"String or binary data would be truncated" and field specifications “Unable to enlist in the transaction” with Oracle linked server from MS SQL Server [<Name of Missing Index, sysname,>] in non clustered index [Execute SQL Task] Error: The value type (__ComObject) can only be converted...
Knowing that the business domain is complex and not always logical or predictable I like to try to accommodate change rather than put unneeded technical obstacles in the way. That's why I have never been a fan of the IDENTITY feature in SQL Server. It's a different matter for other DBMS...
Subramanian, Muralidhar, et al., Performance Challenges in Object-Relational DBMSs, Data Engineering Journal 22, Feb. 1999 pp. 28-32. Welch, Brent B., et al., Pseudo Devices: User-Level Extensions to the Sprite File System, Computer Science Division, Department of Electrical Engineering and...