teradata views

Tags: ar sp for on data BS AD EF asThe result set--select query can be used as an alias as a virtual table with Select*from (Select*from score, grade where score.degree between Low and UPP) as Jibieta ble where rank= ' A '--create view (view can only be based on entity table) CREATE VIEW SHITU1 as select Student.sname,student.sno,score.degree from Stude Nt,score where Student.sno=score.sno go create view shitu2 as Select*from (Select*from score, grade where Score.degree bet Ween Low and UPP) as

Views: A non-real-world table that contains complex queries can also be understood as a result of a query.Add a concept: Temporal table Query (subquery): Is to nest a query again in the query statement, and set the nested query aliasSELECT * from (SELECT nid, NAME from tb1 WHERE >2as AWHERE > ' Alex ';1. Create a view:1 -- format: CREATE view name as SQL statement 2CREATEVIEWas3 selet nid, name from A4 WHERE > 42

Tags: SQL Server tables, views, indexesFirst, the table related1. Create Use[test] Go setansi_nullson go setquoted_identifieron go CREATETABLE[dbo] . [Ceshi] ([Id][int]notnull, [Name][varchar (]null), CONSTRAINT[PK_Ceshi] primarykeyclustered ([Id]asc) with (Pad_index=off,statistics_ norecompute=off,ignore_dup_key=off,allow_row_locks=on, Allow_page_locks=on) on[primary] on[primary] GO--add field comment EXECsys.sp_ addextendedproperty @nam

1. Check the alarm log/u01/app/oracle/diag/rdbms/orcl/orcl/trace/alert_orcl.logReal-time logs: Tail-f/u01/app/oracle/diag/rdbms/orcl/orcl/trace/alert_orcl.logTrace File ADR2. Dynamic performance view (v$) saved in memoryInformation used to access the changing state of the instance memory structure (control file + instance)Session dataWait eventsMemory AllocationsRunning SQLUndo UsageOpen cursorsRedo Log Usage....Different moments can be viewed differently in the dynamic performance view:Startup

A view is a virtual table in a database that, like a real table, contains a series of row and column data with names. Row and column data are referenced by the query that is used to customize the view, and are generated dynamically when the view is referenced.1. Concept of viewsA view is exported from one or more tables and behaves like a table, but the view is a virtual table. Views can be defined on the basis of a view that already exists. On a view

Tags: blog http io os using data SP CSQL Server Import ExportSQL Server Import ExportTools/Materials Import and export data using Microsoft SQL Server Management Studio. Importing and exporting data directly using Microsoft SQL Server Management Studio loses primary keys, views, and so on.The correct method of saving is as follows:First, select the local database that needs to be exportedRight---task---Generate scripts.Follow the wizard

1. Previously, SQL was used without deep learning of the underlying knowledge of the database, especially in terms of how it processes and how locks and underlying data are stored.2. Gradually in the development of the database requirements are slowly highFor example: temporary table-----bi inside, stored procedure insideMaterialized trying to----bi inside likeThe use of db-link in developmentLocking mechanism of 3.oracle:　　　　View of 4.oracle:Database operation of the metadata record, the indivi

Label:/****** Related Parameters ****/Fast_start_parallel_rollback1. There are 3 kinds of values: False,low,high2. Value Meaning: False---Disable the parallel rollback featureLow---Parallel rollback max is 2*cpu_countHigh---Parallel rollback maximum is 4*cpu_count3. This parameter applies to parallel DML or parallel DDL that was not completed before system crash4. Determine the degree of parallelism for parallel rollback5. This parameter applies the rollback phase after the roll-forward is compl

,getdate ()-birthFrom Is_studentwhere GETDATE ()-birth >20(5) A view with an expressionDefines a view of a student's year of birth, including number, name, and year of birthCreate View bt_s (Studentid,studentname,birth)AsSelect Studentid,studentname,getdate ()-birthFrom student(6) Views with grouped statistics:Define a view of each student's academic number and average scoreCreate View S_g (Studentid,grade)AsSelect Studentid,avg (Grade)From gradeGROUP

Tags: sel instance join Department query additions and deletions change what is the name statement--View--encapsulates a complex query statement that is the view.--Advantages: Simplifying query statements--egCREATE VIEW Emp_viewAsSelect Ename as name, job as work, Sal as salary,Dname as department from EMP INNER join DEPTOn EMP. Deptno=dept. DEPTNOWHERE sal>2500SELECT * from Emp_viewWHERE Salary >2000------------------------------------------------What exactly is in the view??--. result set--. S

);--20 violation of the CHECK Constraint for field first_col (First_col Error:constraint failed--As with the previous constraints, the check constraint can also be defined based on multiple columns in the table.Sqlite>CREATE TABLETesttable2 (...> First_col Integer,...> Second_col Integer,...>CHECK(First_col > 0 andSecond_col ...>);second, the modification of the table:SQLite has very limited support for ALTER TABLE commands, simply by modifying the table name and adding new fields. Other feature

Detailed description of how to create and render views in the PHP Yii Framework. The Yii Framework view is part of the MVC mode. It is the code that shows data to end users. in web applications, the methods for creating views and rendering views are described in the Yii Framework of PHP. the yii Framework View is part of the MVC pattern. It is the code used to d

? Previous Article (nested states nested views)Next article (URL Routing )? You can name your views so that you can have more than oneUI-ViewPer template. Let's say you had an application state that needed to dynamically populate a graph, some table data and filters for the table like this: When setting multiple views you need to useViewsProperty on state

1. View(1). What is a view?A view is a database object that provides users with a way to retrieve data from a data table. The user browses some or all of the data that is of interest to the data table through the view, and the physical storage location of the data is still in the table.A view is a virtual table and does not represent any physical data, just a window that is used to view data. Views are not stored in a database as a set of data, only t

Tags: blog http io os using AR for Data 2014Materialized view of Http://www.cnblogs.com/Ronger/archive/2012/03/28/2420962.htmlOracleIn the near future, according to the project business needs to the Oracle materialized view has the contact, searches on the net on this aspect information, facilitates enhances, the collation content as follows:Materialized views are a special physical table, and the materialized view is relative to the normal view. The

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. Types of materialized

Common view Django ' s generic views ... were developed as a shortcut for common usage patterns ... They take some common idioms and patterns that are created and abstracted in view development so that you can quickly write a common view of your data without having to repeat it. -Django Documentation One of the main advantages of CBV is that the they allow you to compose bits of reusable behavior. REST Framework takes advantage of pr

This article describes how to create and render views in the PHP Yii Framework, including the explanation of CWidget small objects and how to render another view in the view, if you need it, refer to the following view as part of the MVC mode. It is the code used to display data to end users. in web applications, a view is created based on The View template. The View template is a PHP script file, which mainly contains HTML code and display PHP code,

1. Overview of Views A view is actually a query SQL statement that displays related data in one or more tables or other views. The view uses the results of a query as a table, so the view can be viewed as a stored query or a virtual table. Views are derived from tables, and all modifications to the view data are ultimately reflected in the base table of the vie

I. Indexed views For years, MicrosoftSQL Server has supported the creation of virtual tables called views. Typically, the main functions of these views are: Provides a security mechanism that restricts users to a dataset in one or more base tables. Provides a mechanism that allows developers to customize how users can view data stored in a base table in a logi