Can anyone give me a good example of when CROSS APPLY makes a difference in those cases where INNER JOIN will work as well? See the article in my blog for detailed performance comparison: INNER JOIN vs. CROSS APPLY CROSS APPLY works better on things that have no simple JOIN condition. This one selects 3 … Read more
you should put those two dates between single quotes like.. or can use keep in mind that the first date is inclusive, but the second is exclusive, as it effectively is ‘2011/02/27 00:00:00’
EDIT: Left Join will work if emp_mgr_id is null.
They’re used in different places. group by modifies the entire query, like: But partition by just works on a window function, like row_number: A group by normally reduces the number of rows returned by rolling them up and calculating averages or sums for each row. partition by does not affect the number of rows returned, … Read more
Is it correct to do the following? No. That will drop the table only if it contains any rows (and will raise an error if the table does not exist). Instead, for a permanent table you can use Or, for a temporary table you can use SQL Server 2016+ has a better way, using DROP TABLE IF … Read more
As per the documentation: FROM (Transact-SQL): The keyword OUTER is marked as optional (enclosed in square brackets). In this specific case, whether you specify OUTER or not makes no difference. Note that while the other elements of the join clause is also marked as optional, leaving them out will make a difference. For instance, the entire type-part of the JOIN clause is optional, in which case … Read more
In SQL Server 2008 you can insert multiple rows using a single SQL INSERT statement. For reference to this have a look at MOC Course 2778A – Writing SQL Queries in SQL Server 2008. For example:
As per the documentation: FROM (Transact-SQL): The keyword OUTER is marked as optional (enclosed in square brackets). In this specific case, whether you specify OUTER or not makes no difference. Note that while the other elements of the join clause is also marked as optional, leaving them out will make a difference. For instance, the … Read more
Stored procedures are a batch of SQL statements that can be executed in a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples. … Read more