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  • Sql 2005 Analysing

    There are some UI operatioon.

         On the programmability folder:

               The Functions folder existing,  which has four components makeup.

           such as  Table-value functions, Scalar-value functions, Aggregate functions, and system functions.

           Table-value functions explain, Transact-sql table-value functions materialize the results of calling the function

    into an intermediate table. Since they use an intermediate table, they can support constraints and unique indexes over

    the results. These features can be extremely useful when large results are returned.

    In contrast, CLR table-valued functions represent a streaming alternative. There is no requirement that the entire set of

    results be materialized in a single table. The IEnumerable object returned by the managed function is directly called by the

    execution plan of the query that calls the table-valued function, and the results are consumed in an incremental manner.

    this streaming model ensures that results can be consumed immediately after the first row is available, instead of waiting for the

    entire table to be populated. It is also a better alternative if you have very large numbers of rows returned, because they do not have to

    be materialized in memory as a whole. for example, a managed table-valued function could be used to parse a text file and return each lines as a  row.

              Scalar-value functions explain, which returns a single value, such as a string, integer, or bit value. Beginning with SQL Server 2005,

    you can creat scalar-valued user-defined functions in managed code using any .net framework programming language. these functions are

    accessible to Transact-SQL or other managed code. For information about the advantages of CLR integration and choosing between managed code and Transact-SQL. .NET Framework SVFs are implemented as method on a class in a .NET Framework assembly. The input parameters and

    the type returned from a SVF can be any of the scalar data types supported by SQL server, except varchar, char, rowversion, text, ntext, image, timestamp, table, or cursor. SVFs must ensure a match between the SQL server data type and the return data type of the implementation method.

    System Functions: Aggregate functions which return a single value, calculated from values in a column.

    Configuration functions,  Cursor functions which return information about cursors

    @@CURSOR_ROWS, CURSOR_STATUS, @@FETCH_STATUS, All the cursor functions are nondeterministtic;

    they do not always return the same results every time they are called with a specific set of input values.

    @@CURSOR_ROWS returns the number of qualifying rows currently in the last cursor opened on the connection.

    To improve performance, mss can populate large keyset and static cursors asynchronously. @@CURSOR_ROWS can be

    called to determine that the number of the rows that qualify for a cursor are retrieved at the time @@CURSOR_ROWS is called.

    CURSOR_STATUS a scalar function that allows the caller of a stored procedure to determine whether or not the procedure has

    returned a cursor and result set for a given parameter.

    CURSOR_STATUS 
     ( { 'local' , 'cursor_name' }  specifies a constant that indicates the source of the cursor is local cursor name.  Is the name of the cursor. A cursor name must conform to the rules for identifiers.

     | { 'global' , 'cursor_name' }  a global cursor name. | { 'variable' , 'cursor_variable' } a local variable.    )

    @@FETCH_STATUS returns the status of the last cursor fetch statement issued against any cursor currently opened by connection.

    Date and Time Functions, Mathematical Functions, Metadata Functions, Other Functions, Rowset Functions,

    Security Functions, String Functions, System Statistical Functions, Text and Image Functions

         On the Database Diagrams folder:

     You can use Server Explorer to create new database diagrams. Database diagrams graphically show the structure of the database.
    Using database diagrams you can create and modify tables, columns, relationships, and keys. additionally, you can modify indexes and

    constraits.

     reference: http://msdn.microsoft.com/en-us/library/ms171977(VS.80).aspx

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  • 原文地址:https://www.cnblogs.com/sandy_liao/p/1750573.html
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