SQL Server 2008, SQL Server 2005, SQL Server 2003, SQL Azure, Oracle Tutorials

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SQL Server 2012 : Delivering A SQL Server Health Check (part 12)

This query is useful because it can show you the overall condition of your indexes as far as fragmentation goes relatively quickly. Heavily fragmented indexes can reduce your I/O performance and your query performance for some types of queries. It can also increase the space required by your data files.

SQL Server 2012 : Delivering A SQL Server Health Check (part 11)

This query identifies the most expensive cached statements for I/O, ordered by average I/O. If your system is showing any signs of I/O pressure, you should definitely take a look at the results of this query.

SQL Server 2012 : Delivering A SQL Server Health Check (part 10)

This query returns the top cached procedures ordered by total logical reads. Logical reads equate to memory pressure, and indirectly to I/O pressure. A logical read occurs when a query finds the data that it needs in the buffer pool (in memory).

SQL Server 2012 : Delivering A SQL Server Health Check (part 9)

This query simply returns cached queries ordered by execution count. This is useful for getting an idea about your typical workload. Knowing which queries are executed the most often, along with their range of execution times and range of rows returned can be very useful information.

SQL Server 2012 : Delivering A SQL Server Health Check (part 8)

After running all the server- and instance-level queries, you should have a fairly good idea of which database or databases are the most resource intensive on a particular instance of SQL Server.

SQL Server 2012 : Delivering A SQL Server Health Check (part 7)

Microsoft has a long-standing recommendation of 300 as a threshold for acceptable PLE, which is often debated in the SQL Server community. One thing that everyone does agree on though is that a PLE value of less than 300 is quite bad.

SQL Server 2012 : Delivering A SQL Server Health Check (part 6)

You can easily create a Microsoft Data Link file on any machine running Windows 2000 or newer by creating a new, empty text file and then changing the file extension from .txt to .udl.

SQL Server 2012 : Delivering A SQL Server Health Check (part 5)

This query will help you zero in on what your SQL Server instance is spending the most time waiting for. Especially if your SQL Server instance is under stress or having performance problems, this can be very valuable information.

SQL Server 2012 : Delivering A SQL Server Health Check (part 4)

This DMV, which was added in SQL Server 2008 R2 SP1, tells you which TCP ports are being used by the TCP Listener — for T-SQL, the Service Broker, and database mirroring.

SQL Server 2012 : Delivering A SQL Server Health Check (part 3)

In SQL Server 2008 R2 Service Pack 1 and later, and in SQL Server 2012, you can learn quite a bit about which SQL Server Services are installed and how they are configured and running from the query shown in Listing 7.

SQL Server 2012 : Delivering A SQL Server Health Check (part 2)

If you installed a new instance of SQL Server 2008 R2 from an .iso image that you downloaded from Microsoft, you would have Build 1600, in the RTM branch. If you then installed SQL Server 2008 R2 SP1, you would have Build 2500, in the Service Pack 1 branch. Any further cumulative updates on this instance would have to be from the Service Pack 1 branch until you moved to a later service pack for SQL Server 2008 R2.

SQL Server 2012 : Delivering A SQL Server Health Check (part 1)

This set of queries is designed to be run on SQL Server 2012. Most of the queries will also work on SQL Server 2008 R2 Service Pack 1 or later, but some will not because Microsoft made a few late-breaking changes to some DMVs in SQL Server 2012.

SQL Server 2012 : Normal Forms (part 3) - Third Normal Form, The Boyce-Codd Normal Form

The third normal form checks for transitive dependencies. A transitive dependency is similar to a partial dependency in that they both refer to attributes that are not fully dependent on a primary key. A dependency is transient when attribute1 is dependent on attribute2, which is dependent on the primary key.

SQL Server 2012 : Normal Forms (part 2) - Second Normal Form

If the entity's primary key is a single value, this isn't too difficult. Composite primary keys can sometimes get into trouble with the second normal form if the attributes aren't dependent on every attribute in the primary key.

SQL Server 2012 : Normal Forms (part 1) - First Normal Form

If the design requires multiple tuples to represent a single item, or multiple items are represented by a single tuple, the table violates first normal form.

SQL Server 2012 : Data Design Patterns (part 4) - Recursive Pattern, Database Design Layers

An associative entity is required to resolve the many-to-many relationship between the component parts being used and the part being assembled. Figure 10 illustrates the BoM (bill of materials) associative entity that has two foreign keys that both point to the Part entity.

SQL Server 2012 : Data Design Patterns (part 3) - Domain Integrity Lookup Pattern

The domain integrity lookup pattern, informally called the lookup table pattern, is common in production databases. This pattern serves to only limit the valid options for an attribute, as illustrated in Figure 7.

SQL Server 2012 : Data Design Patterns (part 2) - Many-to-Many Pattern

Many-to-many relationships are nearly always optional. For example, the many products-to-many special offers relationship is optional because the product and the special offer are each valid without the other.

SQL Server 2012 : Data Design Patterns (part 1) - One-to-Many Pattern, One-to-One Pattern

At the conceptual diagram layer, one-to-one relationships are quite rare. Typically, one-to-one relationships are used in the SQL physical layer to partition the data for some performance or security reason.

SQL Server 2012 : Delivering Manageability and Performance (part 8) - OTHER MICROSOFT TOOLS FOR MANAGING SQL SERVER - System Center Operations Manager

The System Center Operations Manager (SCOM) product is Microsoft’s enterprise monitoring tool and part of the Systems Center suite. SCOM provides a powerful, flexible, and highly configurable platform for building a monitoring solution.

SQL Server 2012 : Delivering Manageability and Performance (part 7) - OTHER MICROSOFT TOOLS FOR MANAGING SQL SERVER - System Center Advisor

The System Center Advisor (SCA) is a cloud-based subscription service that provides configuration reviews and feedback. Part of the System Center manageability product family, it offers detailed customer-specific guidance based on server configuration, and leverages best practices and field knowledge from the Microsoft Customer Service and Support (CSS) organization.

SQL Server 2012 : Delivering Manageability and Performance (part 6) - POLICY-BASED MANAGEMENT - Clustered Indexes

This is a potentially contentious topic, although many DBAs and some organizations mandate that every table must have a clustered index. The following steps describe how to create the condition and policy for reporting through PBM.

SQL Server 2012 : Delivering Manageability and Performance (part 5) - POLICY-BASED MANAGEMENT - Object Naming Conventions

Naming conventions are a good area in environments with a lot of best practice guidance. However, an organization needs to determine which approach will best suit its needs.

SQL Server 2012 : Delivering Manageability and Performance (part 4) - POLICY-BASED MANAGEMENT - SQL Server — Max Degree of Parallelism

The intention of this policy is to ensure that the sp_configure option for Max Degree of Parallelism (MaxDoP) has been optimized (i.e., the current running value is nondefault) on any server with more than four CPUs.

SQL Server 2012 : Delivering Manageability and Performance (part 3) - POLICY-BASED MANAGEMENT - Database — Data and Log File Auto-Grow Increments

This policy checks the auto-growth increments for data and log files to ensure they are optimized given the database size. This particular policy is a good example of how the optimal value for the auto-growth increment varies according to the size of the database.

SQL Server 2012 : Delivering Manageability and Performance (part 1) - POLICY-BASED MANAGEMENT - Enterprise Policy Evaluation

The architecture for the Policy-Based Management framework consists of a Central Management Server where policies are stored; server groups, which are logical containers for servers; and server registrations, which are connections to the target database servers.

SQL Server 2012 : Delivering Manageability and Performance (part 1) - POLICY-BASED MANAGEMENT - Getting Started with PBM

This section describes the steps required to get a PBM deployment up and running. Three phases are required: defining a condition, creating a policy, and evaluating this policy against a local machine.

SQL Server 2012 : Database Basics (part 3) - Foreign Keys, Optionality

The cardinality of the relationship describes the number of tuples (rows) on each side of the relationship. Either side of the relationship may be restricted to allow zero, one, or multiple tuples.

SQL Server 2012 : Database Basics (part 2) - Normalization, Identifying Entities

The first step to designing a database conceptual diagram is to identify the entities (tables). Because any entity represents only one type of thing, it takes several entities together to represent an entire process or organization.

SQL Server 2012 : Database Basics (part 1) - Benefits of a Digital Database, Tables, Rows, Columns, Database Design Phases

A relational database collects related, or common, data in a single list. For example, all the product information may be listed in one table and all the customers in another table.