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Foreign Key and Index Binding

Foreign Key and Index Binding Introductions In this article I am trying to discuss about the foreign key Index binding features. Hope it will be interesting and we can learn something new from it. Point in focus 1.    Foreign Key Definitions 2.    Why Index Binding is necessary 3.    What we …

Array key lookup isset or arraykeyexists or

Array key lookup: isset() or array_key_exists() or @ ? pre { background-color:#444; white-space:pre-wrap; font-size:85%; padding:0px 6px; } Lessons learned: isset() is faster than array_key_exists() array_key_exists() is faster than @ @ is slower than ignoring notices with error_reporting() Here is the code running on a 1.4 GHz machine with PHP 5.4.0: …

FOREIGN KEY Constraint clauses

FOREIGN KEY Constraint clauses Here in this article I am not going to provide the definition of foreign key and how it works. As we all know very well about it.   I am going to illustrate about FOREIGN KEY Constraint clauses. The FOREIGN KEY has two types of clauses …

PRIMARY KEY and INDEX

PRIMARY KEY and INDEX This article is related to PRIMARY KEY and INDEX. A common misconnects is that the PRIMARY KEY is always CUSTERED index.   Before going to the depth of this article I want to ask some common questions. My questions are mentioned bellow. 1.    Is PRIMARY KEY …

Key Lookup

Key Lookup This article is related to Key Lookup operators and how we eliminate them to improve the performance of our query. Introduction Key lookup operator is a bookmark lookup on a table where clustered index exists. It is quite expensive in terms of performance, so we have to eliminate …

Android How to obtain Google API key for Windows

Android – How to obtain Google API key for Windows ? There are some steps to obtain a Google API key for windows. The steps are described in detail below. While you are developing and debugging your application, you will likely be sigining your application in debug mode — that …

What type of Index You Choose for Primary Key

What type of Index You Choose for Primary Key?   In one of my article, someone wants to know more about where we used the clustered index and where to non clustered index. First of all I am thanking you “Anonymous” for giving your valuable time to it. In this …

PRIMARY KEY and NON CLUSTERD INDEX

PRIMARY KEY and NON CLUSTERD INDEX     When we are thinking about the PRIMARY KEY, side by side we are thinking about a clustered index. As the PRIMARY KEY by default create a clustered index. It is good idea that primary key should be CLUSTERED INDEXED. In this article, …

PRIMARY key Vs UNIQUE key

PRIMARY key Vs UNIQUE key This article is created for the beginners only. I find that there are lot of bad concepts related to PRIMARY key and UNIQUE key. In my article I want to clarify all those points related to it. 1.      1.  PRIMARY key and UNIQUE …

Foreign key references in Database

Foreign key references in Database We can find the all the foreign key references by this in current database SELECT a.name FKey,                OBJECT_NAME(a.parent_object_id) ParentTable,                OBJECT_NAME(a.referenced_object_id) RefTable FROM   sys.foreign_keys a   Posted by: MR. JOYDEEP DAS

Which Data Type is good For Primary Key

Which Data Type is good For Primary Key The most important thing of a table is defining the primary key; it could be single column based or the composite primary key.   In my development life, I saw a lot of primary key with different type or patterns. Such as …

Different type of referential actions in foreign key

Different type of referential actions in foreign key Foreign key is an important part of referential integrity. But we often confuse about the foreign key referential actions and their implementations. Here is a beautiful collections that help you to clear your doubts related to it. Foreign keys are defined in …