Overview. MySQL is written in C and C. Its SQL parser is written in yacc, but it uses a homebrewed lexical analyzer. MySQL works on many system platforms. With rank functions in SQL Server 2005, rank rows in your result sets. This tip defines ranking functions in SQL Server and gives examples of rank functions. How to use rank function in SQL Server 2. SQL Server 2. 00. Transact SQL includes a set of functions that lets you rank the rows in your result set. By including. By submitting your personal information, you agree that Tech. Target and its partners may contact you regarding relevant content, products and special offers. You also agree that your personal information may be transferred and processed in the United States, and that you have read and agree to the Terms of Use and the Privacy Policy. SQL Server rank functions in the SELECT clause of your query, you can automatically assign a rank to each row. Beginning Microsoft Sql Server 2008 Administration Amazon' title='Beginning Microsoft Sql Server 2008 Administration Amazon' />The way in which the rows are ranked depends on the function you use. T SQL currently supports four ranking functions ROWNUMBER, RANK, DENSERANK, and NTILE. Ill define these rank functions in SQL Server and show you how they work, but lets first look at the test environment Ill be using to demonstrate these functions. Beginning Microsoft Sql Server 2008 Administration Amazon' title='Beginning Microsoft Sql Server 2008 Administration Amazon' />To obtain the data I needed, I used the following code to create the Sales. Quota table in the SQL Server 2. Adventure. Works sample database USE Adventure. Works. GO Drop Sales. Quotas table if it exists. Beginning Microsoft Sql Server 2008 Administration Amazon' title='Beginning Microsoft Sql Server 2008 Administration Amazon' />IF OBJECTID NSales. Quotas, NU IS NOT NULLDROP TABLE Sales. Quotas. GO Create Sales. Quotas table. SELECT e. First. Name, e. Last. Name, q. Sales. Quota AS Quota,DATENAMEm,q. Quota. Date AS Month, YEARq. Quota. Date AS YearINTO Sales. Quotas. FROM Sales. Sales. Person. Quota. History q. INNER JOIN Human. Resources. v. Employee e. ON q. Sales. Person. ID e. Employee. IDWHERE Sales. Quota BETWEEN 2. ORDER BY e. Last. Name, q. Quota. Date. As you can see, I simply pull data from a couple other tables in the database in order to create a set of meaningful test data. Heres the SELECT statement I use to query the new table SELECTROWNUMBER OVERORDER BY Quota DESC AS Row. Number,RANK OVERORDER BY Quota DESC AS Rank,DENSERANK OVERORDER BY Quota DESC AS Dense. Rank,NTILE5 OVERORDER BY Quota DESC AS NTile,Last. Name, Quota, Month, YearFROM Sales. Quotas. The SELECT statement uses all four ranking functions to rank the rows. I include all the functions in one statement, so you can compare the results returned by each function, as shown in the following result set Row. Number. Rank. Dense. Rank. NTile. Last. Name. Quota. Month. Year. 11. 11. Campbell. January. 20. 02. 21. Vargas. 28. 00. 00. January. 20. 04. 33. Campbell. 26. 70. April. 20. 02. 44. Vargas. 26. 60. 00. January. 20. 02. 55. Ansman Wolfe. 26. January. 20. 02. 66. Jiang. 26. 30. 00. July. 20. 03. 77. Saraiva. 24. 70. 00. Does Windows Vista Support Ssd Trim For Windows. April. 20. 03. 88. Vargas. 24. 40. 00. Ductless Mini Split Installation Nyc Subway here. July. 20. 01. 99. Vargas. 23. 90. 00. January. 20. 03. 10. Campbell. 23. 40. January. 20. 04. 11. Ansman Wolfe. 22. October. 20. 02. 12. Campbell. 22. 60. July. 20. 01. 13. Ansman Wolfe. 22. April. 20. 03. 14. Varkey Chudukatil. January. 20. 03. 15. Ansman Wolfe. 21. July. 20. 021. 5 rows affectedAs you work through the following sections, refer back to the SELECT statement and the result set as necessary to better understand how the ranking function works. ROWNUMBER function. The ROWNUMBER function is the most basic of the ranking functions. As you can see in the result set the Row. Number column, the function numbers each row sequentially, beginning with 1. If you refer back to the query, youll see that the first element in the SELECT clause is the ROWNUMBER function. When you use this function, first specify the function name, followed by the empty parentheses. You do not pass any values into the function. After the ranking function, specify the OVER function. For this function, you pass in an ORDER BY clause as an argument. The clause specifies the column or columns you want to rank. In this case, I am ranking the values in the Quota column in descending order. As a result, the rows in the result set are ranked starting with the highest Quota amount. If you refer again to the result set, youll see the row with the highest Quota value is ranked 1 and the row with the lowest value is ranked 1. The result set contains 1. Thats all there is to using the ROWNUMBER function, and the other ranking functions work in much the same way, only the results are slightly different. RANK function in SQL Server. The next ranking function in the SELECT list is RANK. Once again, you specify the function name, followed by the OVER function, which again includes the ORDER BY clause. However, as you can see in the result set the Rank column. ROWNUMBER function. Yes, the highest Quota value is ranked 1, but, because two rows share the same highest value, they are both ranked 1. When you use the RANK function, all shared values will be ranked the same. But notice that the rank value itself is based on the rows position in the result set, not on the sequential number of the row. For example, the Quota value in the third row is 2. That is the second highest Quota value, yet because it falls in the third row, it receives a ranking of 3, rather than 2. The RANK function skips the 2 because the second row matches the first row. If the fourth row shared the same value as the third row, it would also be ranked as 3. But because the value is lower and it is in the fourth row, it is ranked 4. DENSERANK function. The DENSERANK function takes a different approach. Like the RANK function, the first two rows are assigned a value of 1. However, the DENSERANK function uses sequential numbering, rather than tying the rank to the row number. As a result, the third row is assigned a value of 2 because the Quota column contains the second highest value, and the fourth row is assigned a value of 3 because it is the third highest value, and so on. The ROWNUMBER, RANK, and DENSERANK functions are similar in how they return results. The difference is in whether the numbering is sequential and whether it is tied to the row number. The NTILE function, however, is a bit different than these three functions. NTILE function. If you refer back to the SELECT statement, you can see that when you specify the NTILE function, you pass in an integer as an argument to the function unlike the other ranking functions where you pass in no argument. The NTILE function divides the result set. For example, in the SELECT statement, I specify 5, which means the result set will be split into five groups. Because there are 1. The rows are grouped together based on the value in the Quota column. As a result, the three rows with the highest Quota values are in the first group and receive a ranking of 1. The three rows with the next highest Quota values are in the second group and receive a ranking of 2. Because there are only five groups, the highest ranking is 5, which is assigned to the group with the three lowest Quota values. Again, refer back to the result set to better understand how the NTILE function groups data and then ranks each group. As you can see, rank functions in SQL Server are fairly straightforward, and they make ranking your result set a relatively simple process. Each function gives you a slightly different way to rank the result set. For more information about any of these functions, refer to Microsoft SQL Server Books Online. ABOUT THE AUTHORRobert Sheldon is a technical consultant and the author of numerous books, articles, and training material related to Microsoft Windows, various relational database management systems, and business intelligence design and implementation. You can find more information at  http www.