... | ... | @@ -201,7 +201,7 @@ Use the HAVING clause to verify that no parameter set is missing any sequences. |
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One of the more powerful features of databases is the ability to combine information from multiple tables. There are three main types of table joins: Cross, Inner, and Outer. Cross simply creates all combinations of the joined column values. In our example, a cross join of the Sequences.Sequence and Sets.Parameter_Set columns will generate a row for each row in the Accuracy table. Inner and Outer joins differ on how they treat column values that appear in one table but not the other.
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![joins](Images\sql-joins.jpg)
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![joins](Images/sql-joins.jpg)
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You can perform an INNER JOIN by putting 'INNER JOIN' between two table names, followed by 'ON' and then an equality between two columns from the two tables.
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