Write a query to find second highest salary in oracle

This example uses a unique scan to retrieve a row from the products table. The following statement queries the record for product 19 in the sh. The range in the scan can be bounded on both sides, or unbounded on one or both sides.

Write a query to find second highest salary in oracle

Although indexes can make querying a database faster, they slow changes to the database. The more write-heavy a table is, the more careful you need to be when you add you indexes.

Indexing isn't a one time event, though.

Overview of B-Tree Indexes

As your database grows, you will need to reevaluate your indexing strategy. Indexes will need to be periodically rebuilt to ensure best performance. Changes to client applications, database design, or even your server's hardware will change your indexing strategy. Keep indexes as narrow as possible.

In other words, use the absolute minimum number of columns necessary to get the effect you want. The larger the composite index, the harder SQL Server will work to keep it updated and to use it in queries.

write a query to find second highest salary in oracle

Composite indexes that are also covering indexes are always useful. These indexes are built from more than one column, and all the columns necessary to satisfy a query are included in the index, which is why the index is said to cover the query.

Use clustered indexes on primary keys, by default. Index on search columns. Use a database-level fill factor. Use an index-level fill factor. Index on foreign key columns. The following are some basic guidelines to keep in mind when building you index strategy: Add indexes based on your high-priority and high-execution count queries.

Determine ahead of time what acceptable query execution durations might be based on your business requirements. Instead, add an index and test the query to see that the new index is used. If it is not used, remove it.

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If it is used, test to make sure there are no negative side effects to other queries. Remember that each additional index adds extra overhead to data modifications to the base table. Unless you have a very good reason not to do so, always add a clustered index to each table.

A table without a clustered index is a heap, meaning that the data is stored in no particular order. Clustered indexes are ordered according to the clustered key and its data pages reordered during an index rebuild or reorganization.

Heaps, however, are not rebuilt during an index rebuild or reorganization process, and therefore can grow out of control, taking up many more data pages than necessary. Monitor query performance over time. As your data and application activity changes, so too will the performance and effectiveness of your indexes.

Select clustered index keys that are rarely modified, highly unique, and narrow in data type width. Width is particularly important because each nonclustered index also contains within it the clustered index key.

Clustered indexes are useful when applied to columns used in range queries. With all these factors in mind, remember that you can only have a single clustered index for your table, so choose carefully. Nonclustered indexes are ideal for small or one-row result sets.

Nonclustered indexes should be made on columns containing highly unique data. Avoid wide index keys. Always test narrower composite keys in favor of larger indexes.

Using the Database Engine Tuning Advisor, SQL Server can evaluate your query or batch of queries and determine what indexes could be added or removed in order to help the query run faster.There are multiple ways to get the second highest salary among all Employees. Option 1: Use Subquery.

SELECT MAX(Salary) How will you write a SQL Query to find Max salary and Department name from each department? There are below 3 SQL query to get Second highest salary: Using sub query and IN clause.

SELECT MAX(salary) FROM employees. Oct 14,  · Hi, The Query that you have mentioned above does is it'll check the where condition should equal to 2 or benjaminpohle.com it is 2 then it'll select the required results from TEST table.

I think your query is wrong to get second highest salary. Correct me if I'm wrong. Try this. SELECT Salary FROM (SELECT DISTINCT salary FROM Table_Name ORDER BY Salary DESC) WHERE ROWNUM=2; What .

Dec 22,  · In this section we will write SQL query to get second highest salary of Employee. Before writing query its good to be familiar with schema as well as data in table.

Oct 14,  · Hi, The Query that you have mentioned above does is it'll check the where condition should equal to 2 or benjaminpohle.com it is 2 then it'll select the required results from TEST table.

Sql - How can I select the record with the 2nd highest salary in database Oracle? - Stack Overflow

I think your query is wrong to get second highest salary. Correct me if I'm wrong. Try this. SELECT Salary FROM (SELECT DISTINCT salary FROM Table_Name ORDER BY Salary DESC) WHERE ROWNUM=2; What .

Third or nth maximum salary from salary table without using subquery. I am going to write down different queries to find out the nth highest value of a column. For 2nd highest salary,Change 3 to 2 in above query and for Nth highest salary to N where N = 1,2,3,4.

share . Hi, Sub query: In case of sub queries,for each row that outer query is going to fetch,inner query has to get executed. Exampl: Find the second highest salary in emp table.

How to Find the Second Highest Salary with MySQL Query