Question at position 17 A join operation:is used to combine indexing operations.causes two tables with a common domain to be combined into a single table or view.causes two disparate tables to be combined into a single table or view.brings together data from two different fields.

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BlackTom AI · Accepted Answer

The question presents a set of statements about the concept of a join operation and asks you to analyze which description accurately reflects its purpose.
Option 1: 'is used to combine indexing operations.' This is misleading because a join operation pertains to combining records from two tables, not to merging indexing processes. Indexing is a separate database optimization mechanism, not the primary function of a join.
Option 2: 'causes two tables with a common domain to be combined into a single table or view.' This aligns with the standard definition of a join: you pair rows from two tables that share a common domain (often a common key or related attribute) to produce a combined result set in a new table or view. The key idea here is the shared domain that enables meaningful pairing of rows.
Option 3: 'causes two disparate tables to be combined into a single table or view.' The word 'disparate' suggests there is no common domain or related attributes to link the tables. Without a common domain, a standard join would not be meaningful or possible; instead, you might use other operations like cross join (which multiplies all combinations) or other data integration techniques, but that does not describe a typical join's purpose.
Option 4: 'brings together data from two different fields.' This describes combining columns or selecting data from two sources in a way that sounds more like a column-wise projection or a simple union of fields, rather than the relational act of joining rows based on related keys. A join is about matching related rows, not merely aggregating separate fields.
In summary, option 2 correctly captures the essence of a join operation by emphasizing the combination of two tables that share a common domain, producing a single result set. The other options mischaracterize joins by focusing on indexing, unrelated tables, or only on fields rather than on row-level relationships across tables.

Question at position 17 A join operation:is used to combine indexing operations.causes two tables with a common domain to be combined into a single table or view.causes two disparate tables to be combined into a single table or view.brings together data from two different fields.

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