Features that are available in later versions only are clearly identified, and in most cases workarounds for achieving similar functionality in earlier versions are described. How will that impact what I learn?You will participate fully in the course and acquire the same knowledge and skills as your classmates who participate in the classroom
Oracle 12c Hints
If an index scan is available, the optimizer may choose a nested loops join over a sort-merge join whenever the associated table is the potential inner table of the nested loops. This name can then be used in a hint in the outer query or even in a hint in an inline view to affect query execution on the tables appearing in the named query block
http://dwhlaureate.blogspot.com/2012/06/difference-between-star-snowflake.htmlIn star schema only one join establishes the relationship between the fact table and any one of the dimension tables.A star schema has one fact table and is associated with numerous dimensions table and depicts a star. It is used when a dimensional table becomes very big.In snow flake schema since there is relationship between the dimensions Tables it has to do many joins to fetch the data.Every dimension table is associated with sub dimension table
Difference Between OBIEE AND Oracle BI Applications
http://dwhlaureate.blogspot.com/2012/08/difference-between-obiee-and-oracle-bi.htmlDifference Between OBIEE AND Oracle BI Applications The main difference between OBIEE and Oracle BI Applications is that we use OBIEE for developing our own reports (manually)and dashboard while in prebuilt Apps we just need to deploy them without any customization. Most organizations needs analytic applications pull data from multiple enterprise sources and shed insight into the status and effectiveness of business operations
* (all-column wildcard) Specify the all-column wildcard (asterisk) to select all columns, excluding pseudocolumns, from all tables, views, or materialized views listed in the FROM clause. Oracle processes hierarchical queries as follows: A join, if present, is evaluated first, whether the join is specified in the FROM clause or with WHERE clause predicates
What is a Correlated Subquery? A correlated subquery is a SELECT statement nested inside another T-SQL statement, which contains a reference to one or more columns in the outer query. Depending on the results of the execution of the correlated subquery, it will determine if the row of the outer query is returned in the final result set
Advanced Oracle Tutorials - Subqueries (ctd)
In Oracle SQL, we can also define multiple subqueries and a sub query can reference another sub query as in this second example which reports the names and the number of Oracle tutorials written by authors that have written less than the average number of Oracle tutorials. Therefore to determine which departments have no employees we need to first of all determine which departments have employees and exclude those departments from the set of all departments
Oracle processes hierarchical queries as follows: A join, if present, is evaluated first, whether the join is specified in the FROM clause or with WHERE clause predicates. The result of a partitioned outer join is a UNION of the outer joins of each of the partitions in the partitioned result set and the table on the other side of the join
Oracle SQL subquery types
It is a good idea to discourage the use of the NOT IN clause (which invokes a subquery) and to prefer NOT EXISTS (which invokes a correlated subquery), since the query returns no rows if any rows returned by the subquery contain null values. Verify experience! Anyone considering using the services of an Oracle support expert should independently investigate their credentials and experience, and not rely on advertisements and self-proclaimed expertise
Difference between subquery and join
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(A) (B) Aid Aname Bid Bname 1 ravi 1 sundar 1 ram 1 raj The result should be, Aid Aname Bname 1 ravi Sundar 1 ram 1 raj Is it possible to get the result by Joins without Temp table? Pls. Fill in your details below or click an icon to log in: Email (required) (Address never made public) Name (required) Website You are commenting using your WordPress.com account
What is a correlated subquery?
For each student, two averages are calculated: the average mark of all students in the same class, and the overall average of all students in all classes. Buying human resources software: The adoption phase In this sixth article of a seven-part series on buying HR software, two experts emphasize the importance of user adoption
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http://javarevisited.blogspot.com/2012/07/subquery-example-in-sql-correlated-vs.htmlIn non correlated subquery, inner query doesn't depend on outer query and can run as stand alone query.Subquery used along-with IN or NOT IN sql clause is good examples of Noncorrelated subquery in SQL. Difference between Correlated and NonCorrelated Subquery Now we have seen correlated and noncorrelated subqueries and there example its much easier to understand difference between correlated vs noncorrelated queries
http://sql-plsql.blogspot.com/2011/09/difference-nested-correlated-subquery.htmlCorrelated subqueries improve the SQL performance when:Only a few rows are retrieved through the outer query and especially when outer query's WHERE clause, which limits the number of rows retrieved, can use an index. This is very important if the table or tables against which the inner query is performed is large and the index scan has to retrieve only a small percentage of its rows
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