teradata views

Tags: format encrypt PNG Organization SCH share Physical Results columnFirst, Index:1. Overview: Indexes and views primarily serve as a function of supporting queries and organizing data. Can improve the efficiency of queries, and indexes are a key part of database planning and system maintenance.1.1 Index structure: The index is a separate, physical database structure, and the index relies on table creation, which provides an internal method for arra

Views Sys.user_tab_cols and Sys.user_tab_columns all save the current user's tables, views, andThe column information in the clusters. By retrieving these two tables, you can easily get to the structure of the table.The main column properties are:table_nameTable, view, or clusters namecolumn_nameColumn NameData_typeData typeData_type_modDatatype modifier of the columnData_type_ownerOwner of the datatype of

can query the dictionary view User_updateble_columns to see the columns that can be updated in the join view.You can query the dictionary view User_views to see the view information created by the user. Functions in Views: Views can use a single-line function (consisting of numbers, characters, dates), grouping functions, and expressions.Example 11: This example creates a view with the upper function, noti

1713, R2 has 1870:1 Basic Data dictionary:Dba_tables information for all tables of all users;Dba_tab_columns column (field) information for all users ' tables;Dba_views All view information for all users;dba_synonyms synonym information for all users;Dba_sequences all user sequence information;dba_constraints table constraint information for all users;Dba_indexes summary information for all user indexes;Dba_ind_columns column information for all user indexes;Dba_triggers all user trigger inform

First, views viewA view is a virtual table that itself does not store any data. Only the runtime contains dynamically retrieved data.Eg:select SID, Name, sex, s_num from student, school WHERE sid = 2 and student.sid = Scholl.sid;This simple query involves two of tables. So anyone who needs this data must be familiar with the two tables and the relationships between them. If you want to retrieve additional student information, you must modify the WHERE

with, the index created on the view will be executed, because the view is not related to the original table, it is independent, as follows:Use Adventureworks2012goselect id1,id2,somedatafrom dbo. Viewtablegoselect id1,id2,somedatafrom dbo. Viewlimit with(NOEXPAND)GOCreate an index on a view the problem is more complex, we do not discuss, generally through the general query can solve the problem why bother to view it. We need to take a look at this, please.SummarizeIn this section we talked abou

Atitit Best Practice Attilax Summary of data storage views1.1. View benefits: Improved readability 11.2. conclusion in the principle of readability over performance, human-oriented programming takes precedence over machine-oriented programming and should be prioritized using views 21.3. Disadvantages of views: complex views can sometimes lead to performance de

Label:What is a view? ）1. A view is a database object, a virtual table that is exported from one or more data tables or views, and the data corresponding to the view is not really stored in the view, but is stored in the referenced data table, and the structure and data of the view are the results of querying the data table. 2. Depending on the criteria given when creating the view, the view can be part of a data table or a union of multiple base tabl

1. View)1.1 conceptsView ----- is a "logical table \" defined by the SELECT query statement (which can be a single table or multi-Table query). Only definitions are defined without data, is a \ "virtual table \". when creating a view, you only save the definition information of the view in the data dictionary. instead of copying the actual data to any place, you do not need to allocate storage space for the view in the tablespace. A view is a way to view and manipulate data in a base table. You

The general usage of materialization materialized views are a special physical table, and the materialized view is relative to the normal view. The normal view is a virtual table, the limitations of the application are large, any query on the view, Oracle is actually converted into a query of the views SQL statement. This has no substantial benefit in improving overall query performance.1. The type of mater

From: http://blog.sina.com.cn/s/blog_4d8205e40100gjfe.html To understand the relationships between documents, views, framework windows, and document templates, you must understand their structure.1. First Cwinapp Have a full understandingIt includes and manages applications Program .It has a member variable cdocmanager * m_pdocmanager, which is the manager of the document/window.M_templatelist is a list in cdocmanager. the pointer of all document tem

There are no obvious conceptual differences between the various views in UML, the views are broadly divided into three categories: structural classification, dynamic behavior, and model Management.The structure classification mainly describes the structure members and their interrelation in the system. A class element includes classes, use cases, artifacts, and nodes. The class element lays the foundation f

Hide views View: "Android:visibility"This address: Http://blog.csdn.net/caroline_wendyThe view can optionally be hidden (gone), visible (visible), not visible (invisible).(visible):XML file: android:visibility= "visible"Java code: view.setvisibility (view.visible);not visible (invisible):XML file: android:visibility= "invisible"Java code: view.setvisibility (view.invisible);Hide (Gone):XML file: android:visibility= "Gone"Java code: view.setvisibility

Use RazorEngine to perform UnitTest on Views of ASP. net mvc, Sometimes we need to perform unit tests on the final text produced by Razor (html or xml or. Use Nuget to install RazorEngine. Create an ASP. net mvc project with a test project. Modify Index. cshtml @using TestRazor.Models@model TestModel Test: [TestClass] public class HomeControllerTest {[TestMethod] public void Index () {var config = new TemplateServiceConfiguration (); config. debug = t

Global.asax in Mvctest.webprotected void Application_Start () { myroutestable.registerroutes (routetable.routes); }Resources:EF Codefirst generating entity classes http://www.cnblogs.com/jiajinyi/archive/2013/09/02/3295799.htmlProject separation: http://blog.csdn.net/cmalaya/article/details/8215256http://blog.csdn.net/jk007/article/details/8072680Routes. MapRoute ("Default",//route name' {controller}/{action}/{id} ',//URL with parameterNew {controller = "Home", action =

Android actually provides a simpler class ViewFlipper. ViewFlipper is both a subclass of FrameLayout and a subclass of ViewAnimator. Therefore, ViewFlipper and FrameLayout are similar in functions, however, it can automatically manage the switching between different sub-classes of ViewFlipper, And the animation effect of switching between views can be achieved through the ViewAnimator function. ViewAnimator run to define two Animation actions: InAnima

The difference between this example and the previous example is that AndroidManifest. xml does not define any Style and uses the default Style. [Html]Android: label = "Views/Controls/2. Default Theme"> Android: label = "Views/Controls/2. Default Theme"> Author: mapdigit

Previous: http://www.bkjia.com/kf/201208/146799.html When a direction key or traceball is used to move the UI Focus, there are some UI controls, such as Listview, which can contain sub-UIS (such as list items and Cell items) in the GridView. After the Focus is moved to this type of UI control, you can use the direction keys or traceball to move the selected list items or Cell items within the Listview or GridView. This example introduces a Custom UI control InternalSelectionView. For details abo

common switching methods similar to jump to the next view and the previous view, as well as some common layout methods.You can use the following in activity:@ OverridePublic void onCreate (Bundle savedInstanceState ){Super. onCreate (savedInstanceState );MGallery = new FlingGallery (this );// MGallery. setPaddingWidth (5 );MGallery. setAdapter (mBabyListAdapter );MGallery. setIsGalleryCircular (true );LinearLayout layout = new LinearLayout (getApplicationContext ());Layout = (LinearLayout) Publ

$calledfromwrongthreadexception: Only the original thread, created a view hierarchy can touch its views. What the hell is going on here? The reason is that the view components in the Android system are not thread-safe, and if you want to update the view, you must update it in the main thread, and you cannot perform the updated operation on the child thread.In this case, we will notify the main thread in the child threads, let the main thread