Asked By
BraTz
0 points
N/A
Posted on - 07/14/2011
Most consumer-facing web startups these days use one of the major open source databases, either MySQL or PostgreSQL, to some degree. If you want to prove your worth, it’s a good idea to get down to the nitty gritty and gain some understanding about these databases’ internals.
Please explain to me:
1. What databases indexes are and how they work.
2. Do I need to index a column that is in different table in SQL server?
How does database indexes works?
Hello ,
Database index is data structure which helps retrieval of data from the database faster. Any structure of database which helps faster retrieval of data can be called as a database index.
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One solution of making faster search is making hash tables. Hash table is also a type of database index.
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B-tree is mostly used and the most common database index used, as it has very good performance and gives various ways for comparison of data.
Though the negative point of the database indexes is it is costly to upgrade the index at times. This is something in brief about indexes used in databases.
Hope you got it.
How does database indexes works?
Hi biraTz,
The database indexes is sorted by key strokes, that doesn’t require to be same as in the table because the index is usually small and has few columns on the table. It also speeds up the reading of a row when you are waiting for your search. Indexes serves in a way to find the rows with specification of the columns it refers to, as the larger the table is, the more their cost would be. SQL uses the index if that one is available in it, so you need to check that first so that you confirm that if it is available or not in SQL Server or you need to do something else for index that is different in SQL server.
Thanks.
