sql - How to merge a Group of records in oracle? -

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consider following table,

name    | subject_1    | marks_1    | subject_2    | marks_2    | tom     | maths        | 90         |              |            | tom     |              |            | science      | 50         |  jon     |              |            | science      | 70         | jon     | maths        | 60         |              |            |

how following result 

name    | subject_1    | marks_1    | subject_2    | marks_2    | tom     | maths        | 90         | science      | 50         | jon     | maths        | 60         | science      | 70         |

tried forms of group by did not correct result, maths come under subject_1 , science under subject_2.

use:

  • max
  • group by
 sql> select name,   2    max(subject_1) subject_1,   3    max(marks_1) marks_1,   4    max(subject_2) subject_2,   5    max(marks_2) marks_2   6  t   7  group name;  name subject_1    marks_1 subject_2    marks_2 ---- --------- ---------- --------- ---------- jon  maths             60 science           70 tom  maths             90 science           50  sql>

on side note, need think table design. have 3 columns, name, subject, marks.

if want have separate columns in same table, should have them single row each student. , when have new subject student, update row student, instead of adding new row.


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