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Suppose tbl_1 is a table consisting of 8 rows and tbl_2 is a table consisting of 6 rows, the number of combinations through which the search is performed is . . . . . . .
SELECT tbl_1.i1, tbl_2.i2
	FROM tbl_1 INNER JOIN tbl_2
	WHERE tbl_1.i1 = tbl_2.i2;

A. 14

B. 2

C. 1

D. 48

Answer: Option D

Solution (By Examveda Team)

This question asks about the number of combinations checked when using an INNER JOIN in a SQL query. Let's break it down:
* tbl_1 has 8 rows. * tbl_2 has 6 rows.
* An INNER JOIN combines rows from two tables only if there's a matching value in a specified column (in this case, 'i1' and 'i2').
* The WHERE clause (tbl_1.i1 = tbl_2.i2) further limits the results by requiring the values in the 'i1' column of tbl_1 to be exactly the same as the values in the 'i2' column of tbl_2.
* The number of combinations checked is not simply adding the number of rows in each table. It's about how many times the database needs to compare rows to find matches.
* The correct answer is Option D: 48. To get this, we multiply the number of rows in tbl_1 by the number of rows in tbl_2 (8 rows * 6 rows = 48 combinations). This is because for each row in tbl_1, the database needs to check it against every row in tbl_2 to see if there's a matching 'i1' and 'i2' value.
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