The most flexible way to bulk-load data into SQL Server is to use SSIS. It can also be the fastest, and scaleable way of doing so. There are three different components that can be used to do this, using SSIS, so which do you choose? As always, Rob Sheldon is here to explain the basics.
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The UNION, EXCEPT and INTERSECT operators of SQL enable you to combine more than one SELECT statement to form a single result set. The UNION operator returns all rows. The INTERSECT operator returns all rows that are in both result sets. The EXCEPT operator returns the rows that are only in the first result set but not in the second. Simple? Rob Sheldon explains all, with plenty of examples… Read more
Most of the time, you do not have to worry about implicit conversion in SQL expressions, or when assigning a value to a column. Just occasionally, though, you'll find that data gets truncated, queries run slowly, or comparisons just seem plain wrong. Robert explains why you sometimes need to be very careful if you mix data types when manipulating values.
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Of the big four DML statements in SQL Server, the DELETE is the one least written about. This is odd considering the extra power conferred on the statement by the addition of the WITH common_table_expression; and the OUTPUT clause that essentially allows you to move data from one table to another in one statement.
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With SQL Server 2005, SQL Server introduced some of SQL's window functions, that apply, not to the full set, but a partitioned 'window'. Although the ROW_NUMBER, RANK, NTILE and DENSE_RANK bring great power to TSQL, the full versatility will not be available until SQL Server delivers the full implementation. As usual, Robert Sheldon explains all.
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The INSERT statement in SQL Server is versatile. It now allows the insertion of multiple rows of literal values. It also provides the output clause that solves a number of common problems such as ascertaining the value of identity fields, and other calculated fields in tables, or for auditing the rows that are added to tables. Robert, once again, gives a clear introduction. … Read more
When the SQL MERGE statement was introduced in SQL Server 2008, it allowed database programmers to replace reams of messy code with something quick, simple and maintainable. The MERGE syntax just takes a bit of explaining, and Rob Sheldon is, as always, on hand to explain with plenty of examples.… Read more
In retrospect, it was probably the inclusion of the OUTPUT clause in the MERGE statement that gave SQL Server 2008 its most powerful SQL enhancement.. It isn't the easiest of features to explain, but Bob does it in his usual clear and careful way.… Read more
SQL Server's UPDATE statement is apparently simple, but complications such as the FROM clause can cause puzzlement. Bob Sheldon starts simply, and introduces the more complex forms painlessly. … Read more
The SQL Server common table expression was introduced into standard T-SQL to simplify queries for which a derived table just wasn't suitable. Robert Sheldon explains CTEs in this article.… Read more
Key Performance Indicators, which vary according to the application, are widely used as a measure of the performance of parts of an organisation. Analysis Services makes this KPI data easily available to your cube. All you have to do is to follow Rob Sheldon's simple instructions.… Read more
