Help with SQL Join on two tables

Posted by bladefist on Stack Overflow See other posts from Stack Overflow or by bladefist
Published on 2010-03-17T01:53:38Z Indexed on 2010/03/17 2:01 UTC
Read the original article Hit count: 363

Filed under:

sql

|

joins

I have two tables, one is a table of forum threads. It has a last post date column.

Another table has PostID, UserId, and DateViewed.

I want to join these tables so I can compare DateViewed and LastPostDate for the current user. However, if they have never viewed the thread, there will not be a row in the 2nd table.

This seems easy but I cant wrap my head around it. Advice please.

Thanks in advance.

© Stack Overflow or respective owner

Related posts about sql

SQL SERVER – Concat Strings in SQL Server using T-SQL – SQL in Sixty Seconds #035 – Video

as seen on SQL Authority - Search for 'SQL Authority'
Concatenating string is one of the most common tasks in SQL Server and every developer has to come across it. We have to concat the string when we have to see the display full name of the person by first name and last name. In this video we will see various methods to concatenate the strings. SQL… >>> More
SQL SERVER – Concat Function in SQL Server – SQL Concatenation

as seen on SQL Authority - Search for 'SQL Authority'
Earlier this week, I was delivering Advanced BI training on the subject of “SQL Server 2008 R2″. I had great time delivering the session. During the session, we talked about SQL Server 2010 Denali. Suddenly one of the attendees suggested his displeasure for the product. He said, even though… >>> More
Error with SQL Server Setup 2012 on Windows 2012

as seen on Server Fault - Search for 'Server Fault'
I am trying to install SQL Server on Windows 2012. I was able to finally get the wizard up and running after making some changes on the server, but now it fails no matter what I do with the following error: TITLE: SQL Server Setup failure. SQL Server Setup has encountered the following error: … >>> More
How can I detect which version of SQL (eg SQL 2008 or SQL Azure)

as seen on Stack Overflow - Search for 'Stack Overflow'
I need to detect which version of SQL I am dealing with to perorm various tasks, I need specifically detect if I am on SQL 2008 or SQL Azure. How can I do this with detection code written in SQL? >>> More
Nested SQL Select statement fails on SQL Server 2000, ok on SQL Server 2005

as seen on Stack Overflow - Search for 'Stack Overflow'
Here is the query: INSERT INTO @TempTable SELECT UserID, Name, Address1 = (SELECT TOP 1 [Address] FROM (SELECT TOP 1 [Address] FROM [UserAddress] ua INNER JOIN UserAddressOrder uo ON ua.UserID = uo.UserID WHERE ua.UserID = u.UserID ORDER BY uo.AddressOrder ASC) q ORDER BY AddressOrder… >>> More

Related posts about joins

Rails Joins and include columns from joins table

as seen on Stack Overflow - Search for 'Stack Overflow'
I don't understand how to get the columns I want from rails. I have two models - A User and a Profile. A User :has_many Profile (because users can revert back to an earlier version of their profile): > DESCRIBE users; +----------------+--------------+------+-----+---------+----------------+ |… >>> More
SQL Joins on varchar fields timing out

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I have a join which deletes rows that match another table but the joining fields have to be a large varchar (250 chars). I know this isn't ideal but I can't think of a better way. Here's my query: DELETE P FROM dbo.FeedPhotos AS P INNER JOIN dbo.ListingPhotos AS P1 ON P.photo = P1.feedImage INNER… >>> More
Joins and UI Binding with the Entity Framework

as seen on Internet.com - Search for 'Internet.com'
Learn how to build queries with the Entity Framework that involve multiple tables as well as binding in the UI with the EntityDataSource. >>> More
Fetching Data from Multiple Tables using Joins

as seen on Internet.com - Search for 'Internet.com'
Applying normalization to relational databases tends to promote better accuracy of queries, but it also leads to queries that take a little more work to develop, as the data may be spread amongst several tables. In today's article, we'll learn how to fetch data from multiple tables by using joins. >>> More
App Engine joins the Google over IPv6 Program

as seen on Google Code - Search for 'Google Code'
The Google over IPv6 program allows ISPs with good connectivity to request IPv6 access for most Google services. In about a week, we'll be adding Google App Engine... >>> More