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 Related Questions Explain the use of the WHERE clause. WHERE is used with a relational statement to isolate the object Explain the use of the WHERE clause. WHERE is used with a relational statement to isolate the object element or row. An outer join includes rows from tables when there are no matching values in the tables. Latest Answer : 3 types. Left outer Join----left table unmatched valyes are included.Right Outer Join---right table unmatched values are included.Full outer Join----Both table unmatched values are selected. ... A subselect is a select which works in conjunction with another select. A nested select is a kind of subselect where the inner select passes to the where criteria for the outer select. The explain statement provides information about the optimizer's choice of access path of the sql. Latest Answer : The EXPLAIN statement obtains information about access path selection for an explainable statement. A statement is explainable if it is a SELECT or INSERT statement, or the searched form of an UPDATE or DELETE statement.The information obtained is placed ... Explain transactions, commits and rollbacks in DB2. In DB2 a transaction typically requires a series Explain transactions, commits and rollbacks in DB2. In DB2 a transaction typically requires a series of updates, insertions and deletions that represent a logical unit of work. A transaction puts an implicit lock on the DB2 data. Programmers can use the COMMIT WORK statement to terminate the transaction creating smaller units for recovery. If the transaction fails DB2 uses the log to roll back values to the start of the transaction or to the preceding commit point. DB2 can implement a join in three ways using a merge join, a nested join or a hybrid join. Explain the differences. A merge join requires that the tables being joined be in a sequence; the rows are retrieved with a high cluster ratio index or are sorted by DB2. A nested join does not require a sequence and works best on joining a small number of rows. DB2 reads the outer table values and each time scans the inner table for matches. The hybrid join is a nested join that requires the outer table Compare a subselect to a join. Any subselect can be rewritten as a join, but not vice versa. Joins are usually more efficient as join rows can be returned immediately, subselects require a temporary work area for inner selects results while processing the outer select. A Cartesian product results from a faulty query. It is a row in the results for every combination in the join tables. Latest Answer : Reuse means you can use the same cluster for further use. Remember it alternate index doesn't support for reuseble cluster.Upgrade means when the base cluster is opened for processing then the alternate index is updated automatically. ... Latest Answer : hi, sys cat will give all data sets that are catalogged ang sys ibm will give all data sets. ...
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