Search results
Results from the WOW.Com Content Network
A surrogate key is frequently a sequential number (e.g. a Sybase or SQL Server "identity column", a PostgreSQL or Informix serial, an Oracle or SQL Server SEQUENCE or a column defined with AUTO_INCREMENT in MySQL). Some databases provide UUID/GUID as a possible data type for surrogate keys (e.g. PostgreSQL UUID [3] or SQL Server ...
An identity column differs from a primary key in that its values are managed by the server and usually cannot be modified. In many cases an identity column is used as a primary key; however, this is not always the case. It is a common misconception that an identity column will enforce uniqueness; however, this is not the case. If you want to ...
Dimension tables often use primary keys that are also surrogate keys. Surrogate keys are often auto-generated (e.g. a Sybase or SQL Server "identity column", a PostgreSQL or Informix serial, an Oracle SEQUENCE or a column defined with AUTO_INCREMENT in MySQL). The use of surrogate dimension keys brings several advantages, including: Performance.
The default start and increment values might reveal information about a table that it is desired not to reveal to people viewing individual table rows. For example, using an AutoNumber field for a customer ID might reveal information that it is desirable not to reveal to, say, customer number 6.
In the relational model of databases, a primary key is a designated attribute that can reliably identify and distinguish between each individual record in a table.The database creator can choose an existing unique attribute or combination of attributes from the table (a natural key) to act as its primary key, or create a new attribute containing a unique ID that exists solely for this purpose ...
Sun Bowl - Louisville vs. Washington. Time/TV/location: 2 p.m. ET, CBS, El Paso, Texas. Why watch: Oh what might have been for Louisville, which won at Clemson in dominant fashion and came within ...
COST data by YCharts. 3. Value stocks increase in popularity. Many stocks now trade at premium prices thanks to the huge gains of the last couple of years. Sooner or later, though, investors will ...
Yields: 6-8 servings. Prep Time: 20 mins. Total Time: 12 hours 20 mins. Ingredients. 1 c. cold eggnog. 1/2 tsp. ground nutmeg, plus more for garnish. 1 (3.4-oz.) box instant vanilla pudding mix