COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Use long form of field name
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Remove that field name from the query
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Require unique fieldnames for all
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No such thing as ambiguous error
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Detailed explanation-1: -This means two columns have the same column name-that is the “Name” column. The SQL Machine is confused as to which “Name” out of the two tables you are referring to. It is ambiguous-not clear. To clarify this, add the alias of either or both TABLE1 or TABLE2 to the columns having the same name.
Detailed explanation-2: -You may see an error that says something like Column ‘id’ in field list is ambiguous . This error means that there is a field name that is present in more than one table, so it needs to be scoped with the table name to avoid ambiguity: using orders.id instead of just id will resolve the issue.
Detailed explanation-3: -Ambiguous references can also be avoided without the use of the table designator by giving unique names to the columns of one of the object tables using the column name list following the correlation name. Two or more object tables can be instances of the same table.
Detailed explanation-4: -Ambiguity errors occur when erasure causes two seemingly distinct generic declarations to resolve to the same erased type, causing a conflict.
Detailed explanation-5: -One common error when performing SQL joins is the “ambiguous column name” error. This type of error occurs when you attempt to join in two or more tables and more than one column of the same name appears in more than one of the tables.