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I have a few doubts about indexs in databases:

  1. Suppose i have a table 'student':

    id  name  age  class  roll_no
1   vijay 24   12     1007
2   vinay 25   10     1008

    if i write select * from student where name='vijay';

    1. If i have index on column name then it will search for index name in index table ? Can i check index table data how does it store data ?
    2. If i don't have index then it will search for only name column or entire row starting from first row's id, then name and so on.... and then second row ?
    3. Is indexes can be created on non unique column's ?
Jim Jones
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Deepak Kumar
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1 Answers1

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Read here for more info on indexes. http://postgresguide.com/performance/indexes.html

Edit: Rectified for postgresql

Google a bit before asking questions.

Yuvraj Jaiswal
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