![]() A cross join should only be used with extreme caution.In an inner join only data that meets the ON condition is read. Join all data is read first before the condition is evaluated. Inner join with an identical ON condition. ![]() A cross join with a WHERE condition has the same result as an A cross join behaves like an inner or outer join whose ON condition isĪlways true.If the left and right side are switched, the result remains the same. An inner join or a cross join between two individual data sources is commutative.A WHERE condition for a SELECT statement with joins affects the result set created using the joins.These restrictions are documented in the corresponding clauses. For example, a join expression cannot be used together with the addition Certain restrictions apply to other clauses in the current SELECT statement.The number of rows in the result set of the cross join is the product of the number of rows of both joined result sets. This result set contains all possible combinations Of the rows in the result set of the right side. The cross join joins the columns of the rows in the result set of the left side with the columns The cross join forms a cross product of the result set of the left side and the result set of the right The columns on the other side that do not meet the condition sql_cond are filled with OUTER JOIN, at least one row is created in the result set, even if no rows on the other side Row on the left side as LEFT OUTER JOIN or on the right side as RIGHT The difference is that, for each selected The outer join creates the same result set as the inner join. If there are no rows in the result set of the left and right sides that meet sql_cond, no row is created in the resulting result set. ![]() Of rows for whose columns the join condition This result set contains all combinations Rows in the result set of the right side into a single result set.
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