Now, I am going to describe this process on a particular example to check whether it will allow us to determine the use of the object comparison by value in general and thus, to simplify a sample of comparing objects by value – class instances that represent reference types.
In my previous publication, I described the fullest and the most correct way to compare objects by value – class instances that represent reference types in the .NET framework.
Now, I am going to determine how it is possible to modify the proposed method to compare instances of the structs that represent value types.
There is an information system that I administer. The system consists of the following components:
1. MS SQL Server database
2. Server application
3. Client applications
These information systems are installed on several objects. The information system is used actively 24 hours a day by 2 to 20 users at once on each object. Therefore, you cannot perform routine maintenance all at once. So, I have to «spread» SQL Server index defragmentation throughout the day, rather than defragmenting all the necessary fragmented indexes at one stroke. This applies to other operations as well.
In this article, we will discuss typical errors that newbie developers may face with while designing T-SQL code. In addition, we will have a look at the best practices and some useful tips that may help you when working with SQL Server, as well as workarounds to improve performance.
In the previous article, we analyzed how to compare objects by value on a particular example with the Person class that includes:
- Overriding the GetHashCode() andObject.Equals(Object) methods;
- Implementation of the IEquatable (Of T) interface;
- Implementation of the type-specific static method Equals(Person, Person) and operators ==(Person, Person), !=(Person, Person).
Sooner or later, a DB administrator would like to have a performance indicator for SQL Server queries. As we all know, running Profiler for 24 hours will lead to a considerable system load and therefore, it cannot be considered an optimal solution for databases used in the 24/7 mode.
So, how can we detect the state of SQL Server queries? How can we run trace for detected query-related problems without the human input?
In this article, I will provide an implementation of the SQL Server performance indicator for queries, stored procedures and triggers, as well as its usage for the trace run. Read More
The World Wide Web offers a bunch of information on SQL Server index defragmentation or SQL Server index rebuild. However, most of the recommendations refer to databases that have minimum load time (mostly, at night).
And what about databases that are used for both, data modification, and retrieving information on a 24/7 basis?
In this article, I will provide a mechanism for automating SQL Server index defragmentation implemented in a database used in the company I work for. This mechanism allows defragmenting required indexes on a regular basis since index fragmentation takes place constantly in the 24/7 system. Often, this is not enough to perform index defragmentation once a day. Read More
What are unique key constraints?
A unique constraint is a rule that restricts column entries to unique. In other words, this type of constraints prevents inserting duplicates into a column. A unique constraint is one of the instruments to enforce data integrity in an SQL Server database. Since a table can have only one primary key, you can use a unique constraint to enforce the uniqueness of a column or a combination of columns that do not constitute a primary key.
Creating a unique constraint on a column automatically creates a unique index. This way SQL Server implements the integrity requirement of the unique constraint. Therefore, when attempting to insert a duplicate value into a column, on which a unique constraint is defined, the Database Engine will detect the unique constraint violation and issue a corresponding error. As a result, the row with the duplicate values will not be added to a table.
Now, we will explore a type-specific implementation of how to compare objects by value including the IEquatable(Of T) generic interface and overload of “==” and “!=” operators.
Type-specific comparison of objects by value allows achieving:
- a more stable, scalable and mnemonic (readable) code through overloaded operators;
- higher performance.
Recently, I was involved in the development of the functionality that required a fast and frequent transfer of large volumes of data to disc. In addition, this data was supposed to be read from disk from time to time. Therefore, I was destined to find out the place, the way and the means for storing this data. In this article, I will briefly review the task, as well as investigate and compare solutions for completion of this task.
Context of the task: I work in a team that develops tools for relative database development (SQL Server, MySQL, Oracle). The tool range includes both, standalone tools, and add-ins for MS SSMS.
Task: Restoring documents that were opened at the moment of IDE closing at the next start of IDE. Read More