Answer : Explanation : Both these are used to combine the results of different SELECT statements. UNION - Selects only distinct values UNION ALL - Selects duplicate values also Syntax: SELECT column_name(s) FROM table1 UNION / UNION ALL SELECT column_name(s) FROM table2;Notice that each SELECT statement within the UNION must have the same number of columns. The columns must also have similar data types. Also, the columns in each SELECT statement must be in the same order.
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