Logins and Users are basic security concepts in SQL Server. They are often, and incorrectly, considered to be pretty much one in the same so it is sometimes confusing to some SQL Server users. Another important security concept tied to a login and user in SQL Server is Security Identifiers (SID). This article will explain these concepts through a step-by-step demonstration. This article will focus on the Windows login and provide some specific usage scenarios.
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This article explains lock issues in SQL Server with DDL statements including SELECT INTO clause.
Use of explicit transaction is common in SQL Server development. Sometimes a developer might inadvertently specify a Data Definition Language clause within a long running explicit transaction, similar to the structure below, within a SQL Server object such as a stored procedure.
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It is common assumption that an Index Seek operation in a query plan is optimal when returning a low number of output rows. In a scenario involving residual predicates, an Index Seek operation could be reading a lot more rows than it needs into the memory, then each row is evaluated and discarded in memory based on the residual predicate and returns low number of output rows.
This article will explain the concept and the impact of Residual Predicates in a SQL Server Index Seek operation.
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If you are maintaining a very large database, you might be well aware of the pain to perform update statistics on a very large table.
This article introduces incremental statistics which is available from SQL Server 2014 highly simplifies statistics management on very large partitioned tables.
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