What is the difference between join and union.
Answer Posted / sompalli krishna
Join: joins are used to combine the columns from one or
more tables(join using one table is possible for self
join).output should B more than one column.
It is constraint based.Columns r joined based on similar
column names and datatypes also on both the tables.
union: union is used to combine the columns from one or
more tables.Output should B one column.
It is not constraint based.Any no. of columns can be
combined without using any condition.But the data types
should be same immaterial to column names.
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