Term
| What is a Cartesian product? |
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Definition
A mathematical operation which returns a set (or product set) from multiple sets. A x B. |
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Term
| What does a Cross Join do? |
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Definition
It will produce rows which combine each row from the first and second table. |
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Term
| What does a Inner Join do? |
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Definition
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It creates a new result table by combining values of two tables (A and B) based upon the join-predicate. |
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Term
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Definition
It uses a specific type of comparator-based join, that uses only equality comparisons in the join-predicate. |
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Term
| What does a Natural Join do? |
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Definition
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It is a type of equi-join where the join-predicate arises implicitly by comparing all columns in both tables that have the same column-names in the joined tables. |
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Term
| What does a Left Outer Join do? |
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Definition
All records of the 'left' table (A) are matched to a corresponding value in the 'right' table (B). If nothing matches, NULL will show instead.
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Term
| What does a Right Outer Join do? |
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Definition
All records of the 'right' table (B) are matched to a corresponding value in the 'left' table (A). If nothing matches, NULL will show instead.
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Term
| What does a Full Outer Join do? |
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Definition
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It combines the effects of applying both left and right outer joins. Where records in the full outer joined tables do not match, the result set will have NULL values for every column of the table that lacks a matching row. |
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Term
| What does a Self Join do? |
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Definition
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It joins a table with itself. |
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