what is the difference between joins and set operators.i am
always confusing with two,can u pls kindly help me .
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Answer / amretha
For set operators the columns in the tables must be the same.Where as for Joins if one column is same its enough to join two or more tables.
| Is This Answer Correct ? | 19 Yes | 2 No |
Answer / jyoti
Set - Comparison is to be performed on Tables.
Join- Comparison is to performed on rows of tables.
| Is This Answer Correct ? | 9 Yes | 3 No |
joins project the data from more than one table vertically
based on common cloumns among the tables.
in case of set operators, its combine(merge) data horizantally, programer have to manage the correct logic and sence in the data. set operators uses for data presentation.
| Is This Answer Correct ? | 5 Yes | 6 No |
Answer / mahesh
suppose if we have joined two tables display the both table column names whatever we are giving and incase if we are use set operators columns not displyaed both tables.only first select query columns only displayed.
| Is This Answer Correct ? | 1 Yes | 5 No |
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