Simple MS SQL count question
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I have this SQL
DECLARE @url varchar(100) SET @url = 'http://mysite.com/%' SELECT [UserSessionSequenceID] ,[SiteID] ,[Referer] ,[Timestamp] ,ROW_NUMBER() over (PARTITION BY [Referer] ORDER BY referer DESC) AS sort FROM [tblSequence] WHERE [Referer] IS NOT NULL AND [Referer] NOT LIKE @url AND siteID = 15
Want to count unique referer - problem is that this SQL returns ALL matches and count those one by one. I only want the count for each unique referer (and still exsluding the @url with like).
How to do that?
SELECT [Referer], Count([Referer]) as RefCount FROM [tblSequence] WHERE [Referer] IS NOT NULL AND [Referer] NOT LIKE @url AND siteID = 15 GROUP BY [Referer]
Putting Order back in (should that really be required) depends on your exact requirements.
question badge. Considering the database schema displayed in the SQLServer-style diagram below, write a SQL query to return a The partition_by_clause divides the result set produced by the FROM clause into partitions to which the COUNT function is applied. If not specified, the function treats all rows of the query result set as a single group. The order_by_clause determines the logical order of the operation. See OVER Clause (Transact-SQL) for more information.
Use DENSE_RANK not ROW_NUMBER if you require row data instead of an aggregate
These exercises allow you to try out your skills with the COUNT function. You will be given questions that you need to solve. After each exercise, we provide the The SQL COUNT function returns the number of rows in a query. NULL value will not be counted. SQL COUNT Syntax. SELECT COUNT (expression) AS resultName FROM tableName WHERE conditions. The expression can be *, column name or DISTINCT column name. All these 3 expressions work with MS SQL Server, Oracle and mySQL. SQL COUNT Examples.
DECLARE @url varchar(100) SET @url = 'http://example.com/%' SELECT distinct [UserSessionSequenceID] ,[SiteID] ,[Referer] ,[Timestamp] ,count(*) over (PARTITION BY [Referer] ORDER BY referer DESC) AS sort FROM [tblSequence] WHERE [Referer] IS NOT NULL AND [Referer] NOT LIKE @url AND siteID = 15
QtySold; Code snippet Chap07.sql This time you see more than one action and and NTILE, you can have SQL count off your results to determine where each beginning with a relatively simple question — how do the sales staff rank, first to The SQL Join clause is used to combine records (rows) from two or more tables in a SQL database based on a related column between the two. There are four different types of JOINs in SQL: (INNER) JOIN : Retrieves records that have matching values in both tables involved in the join.
Read 50 most frequently asked SQL query questions and improve your SQL skills. To get you started, But you can't start until the required sample data is not in place. You can SELECT COUNT(*) FROM worker WHERE DEPARTMENT = 'Admin'; The following SQL Server query returns the nth highest salary: SELECT The test contains 25 questions and there is no time limit. The test is not official, it's just a nice way to see how much you know, or don't know, about SQL. Count Your Score. You will get 1 point for each correct answer. At the end of the Quiz, your total score will be displayed. Maximum score is 25 points.
Note that the third SQL command set in Figure 7.21 uses the COUNT(*) command to answer the question, “How many rows in the values. note Note to MS Access Users MS Access does not support the use of COUNT with the DISTINCT clause. Although that query seems simple enough, the SQL command sequence: Email questions to: email@example.com. WideWorldImporters sample database. WideWorldImporters (WWI) is a sample database that showcases database design using current features, tools and design techniques. WideWorldImporters downloads include an OLTP and an OLAP database which are built to run on SQL Server 2016 and later.
In this guide you will find a collection of real world SQL interview questions some sql practice problems which you can solve right away which is simply the Most modern database management systems like MySQL, Microsoft SQL Server, SELECT COUNT(studentId), country FROM myDB.students WHERE country != The COUNT () function returns the number of records returned by a select query. Note: NULL values are not counted. COUNT (expression) Parameter Values. Required. A field or a string value. Technical Details. SQL Server (starting with 2008), Azure SQL Database, Azure SQL Data Warehouse, Parallel Data Warehouse. SQL Server Functions.
- Looks good - what if I want to add the [timestamp] in the overall where clause? AND ([Timestamp] > DATEADD(dd, -1, (LEFT(GETDATE(),12))))
- This was my first thought, but then I realise OP wants unique referer count and unaggregated row data in one call. Sorry everyone for my previous typo...
- Seo20 - please indicate whether you're looking for an answer like gbn has indicated, or aggregation like I'm doing. I suspect gbn's method is more what you want. But what's holding you back from just adding the WHERE statement you just gave in your comment? (In either solution)
- Change "ROW_NUMBER()" to "DENSE_RANK()" in the query you posted