Aula exemplo para atividade e-learning

1. SQL Server™ .NET
Programmability
José A. Blakeley
Architect
SQL Server
Background
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Transact SQL (T -SQL)
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SQL Server’s database programming language
Includes:
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SQL DDL, SQL DML
Variables, assignment, iteration, procedures, functions
.NET Platform
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.NET runtime (Common Language Runtime)
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Verifiable Intermediate Language
Managed memory – garbage collection
Multiple languages (e.g, C#, C++, Cobol)
(e.g ,
Frameworks library (e.g., GUI, Files, XML)
Assemblies – New Dynamic Link Libraries
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Contain code + metadata (class definitions, assembly
dependencies)
Unit of code deployment, security, versioning
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
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2. Outline
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Motivation
Basic Infrastructure
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SQL features
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Hosting overview
Data access inside process: ADO.NET
SQL types
Server assemblies
Functions, procedures, triggers
Types and aggregates
Summary
Motivation
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Broaden the set of languages for running
datadata -intensive business logic in server
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Packaged as .NET assemblies
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Verifiable, secure
Deployed to SQL Server as
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IT Developers and ISVs
Multiple languages: Visual Basic ®, C#, C++, J#, …
Same mid - and server -tier data access model
midserverSame tools: IDE, project model, debugging, …
TransactTransact-SQL still supported
Functions, procedures, triggers, types
Basis for SQL Server Extensibility
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
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3. Development Steps
VB, C#, C++
VS
Project
Build
Runtime
hosted inside
SQL Server
SQL Queries:
select
sum(tax(sal,state)
sum(tax(sal,state) )
from Emp where county
= ‘King’
Assembly:
“TaxLib.dll”
TaxLib.dll”
SQL Data Definition:
create assembly …
create function …
create procedure …
create trigger …
create type …
SQL Server
Basic Infrastructure
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Hosting common language runtime
inside SQL Server
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Data access in process
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4Ss: Safety, security, scalability, speed
Run verified, type-safe code inside
typeprocess
Multiple languages
Based on ADO.NET
Same data access programming model
as middle -tier
middle-
SQLTypes
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SQL type semantics in managed code
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
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4. Hosting .NET Runtime
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Safety
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Prevent user code from corrupting the server
process
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Use runtime code permissions to control user code
when calling
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Verifiable code
Unmanaged APIs, user interface, threads, synchronization
Security
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Authorized access to SQL Server data from user
code via SQL Server authorization model
Authorized access to system resources from user
code via runtime code permissions
Administrators control permissions given
to assemblies
Three Code Permission Sets
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SAFE
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Execute & data access permission
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No access to resources outside SQL Server
No unmanaged calls
Must be verifiable
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EXTERNAL_ACCESS
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SAFESQL + access to external resources (Net, File
permissions)
Requires EXTERNAL ACCESS permission to create
SQL Server will impersonate the caller
Must be verifiable
UNRESTRICTED
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No controls: Can call unmanged code, can be un-verifiable
unOnly Administrators can create
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
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5. Hosting .NET Runtime
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Scalability
As many concurrent users as, as fast as
TransactTransact-SQL
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Integrated SQL Server and runtime threads
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Collaboration between SQL Server and GC
SQL Server becomes OS to the .NET runtime
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Speed
Efficient data access in process
Compiled user code, not interpreted as
TransactTransact-SQL
Fast transitions in/out of runtime
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Speed: Functions
.NET function vs. Transact-SQL inline
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.NET function vs. Transact-SQL function
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200
1000000
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Query time (ms)
Query time (ms)
800
100000
10000
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1000
Integer ops per func call
100
.NET func
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10 TSQL inline
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100
1000
10000
Integer ops per call
.NET functions approximating speed of TransactTransact.NET func
TSQL func
SQL inline expressions
.NET framework functions much faster than
TransactTransact-SQL functions for complex expressions
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
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6. Outline
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Motivation
Basic Infrastructure
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SQL features
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Hosting overview
Data access inside process: ADO.NET
SQL types
Server assemblies
Functions, procedures, triggers
Types and aggregates
Summary
ADO .NET Data Access
Controls,
Designers,
etc
XSL/T, X -Path,
XValidation, etc
XmlDataXmlDataDocument
XmlReader
XmlText- XmlNodeXmlText- XmlNode Reader
Reader
DataSet
Sync
SQL Server
Managed
Managed
Managed
Provider
Provider
Provider
XmlReader
XmlText- XmlNodeXmlText- XmlNode Reader
Reader
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
6

7. Data Access Inside SQL
using System.Data.SqlServer;
System.Data.SqlServer;
using System.Data.SqlTypes;
System.Data.SqlTypes;
public class ShippingCosts {
public static SqlMoney FreightByShipper( string ship ) {
FreightByShipper(
SqlCommand cmd = SqlContext.GetCommand( );
SqlContext.GetCommand(
cmd.CommandText = "select sum(o.freight) as freight " +
"from orders o join shippers s on o.shipvia = s.shipperid " +
"where s.companyname = @CompanyName " ;
@CompanyName
SqlParameter param = cmd.Parameters.Add("@CompanyName",
cmd.Parameters.Add("@CompanyName",
SqlDbType.NVarChar,
SqlDbType.NVarChar, COMPANY_NAME_COL_LENGTH);
param.Value = ship;
ship;
SqlMoney amount = cmd.ExecuteScalar( );
cmd.ExecuteScalar(
return amount;
}
}
SQL Types
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Reduce impedance mismatch between
programming language and data
Consistent expression evaluation in
midmid- and server-tier programming
serverSQL Types library
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Managed classes: System.Data.SqlTypes
Provide SQL semantics
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Nullability, threeNullability , three-valued logic
Precision and scale in operations
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
7

8. SQL Types Example
Tax function using SQL types
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using System;
using System.Data.SQLTypes
;
public class myFinances
{
public static SQLDouble tax( SQLDouble sal )
{
if ( sal < 50000.0 ) return sal * 0.15;
0.15;
if ( sal >= 50000.0 && sal <= 90000.0 ) return sal * 0.23
else return sal * 0.35;
0.35;
}
}
SQLDouble makes function NULL-aware
NULL-
Outline
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Motivation
Basic Infrastructure
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SQL features
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Hosting overview
Data access inside process: ADO.NET
SQL types
Server assemblies
Functions, procedures, triggers
Types and aggregates
Summary
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
8

9. SQL Features
Assemblies
Functions
Procedures
Triggers
Types
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Creating An Assembly
CREATE ASSEMBLY geom FROM ‘m1typesgeometry.dll’
‘ m1types
WITH PERMISSION_SET = SAFE
WITH AUTOREGISTER
DROP ASSEMBLY lib_geom
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Assemblies stored in database
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Safe (default), external access, unrestricted
Autoregister functions
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Backup, restore with data
Code permissions assigned per assembly
Using .NET custom attributes
Assembly benefits
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SelfSelf-describing metadata: Types, file dependencies
Unit of code deployment: Permissions, versioning
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
9

10. Altering An Assembly
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Cannot invalidate persistent data or indexes
Implies
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No tables with columns of UDT from this assembly
No indexes on functions of this assembly
Force option allows ALTER even if persistent
dependencies exist
Packaging considerations
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Place routines and types in different assemblies
Creating A Function
CREATE FUNCTION distance (
@x1 int, @y1 int, @x2 int, @y2 int ) RETURNS float
int,
int,
int,
EXTERNAL NAME ‘geom:CPoint.Distance’
‘geom:CPoint.Distance’
DETERMINISTIC
RETURNS NULL ON NULL INPUT
DROP FUNCTION distance
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Functions called from queries
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Can be scalar or table -valued
Static class functions
Deterministic functions
Using a function in a query
SELECT s.name FROM Supplier s
WHERE dbo.distance ( s.x, s.y, @x, @y ) < 3
dbo.distance(
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
10

11. Creating A Procedure
CREATE PROCEDURE check_inventory
EXTERNAL NAME ‘events:CInventory.check_level’
‘events:CInventory.check_level’
DROP PROCEDURE check_inventory
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Procedures not called from queries
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Can contain SQL queries, updates or DDL
Can return results directly to client
Creating A Trigger
CREATE TRIGGER supplier_event ON supplier
AFTER INSERT, UPDATE
EXTERNAL NAME ‘events:CNotif.Supp_Event’
‘events:CNotif.Supp_Event’
DROP TRIGGER supplier_event
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Similar to procedures, plus
Access to inserted, deleted tables
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
11

12. Creating A Type
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Create or drop a type
CREATE TYPE Point
EXTERNAL NAME ‘geom:Point’
‘geom:Point’
DROP TYPE Point
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Using a type
CREATE TABLE Supplier (
id
INTEGER PRIMARY KEY,
name
VARCHAR(20),
location
Point )
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Using a type method in a query
SELECT s.name FROM Supplier s
WHERE s.location::distance( @point ) < 3
Query Optimization
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Automatically gather function statistics
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Reorder of predicate evaluation
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Based on execution cost and statistics
Function indexes
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Value histograms, execution cost
Speed up expensive functions
Extends computed column indexes
and index views
Implied and residual predicates
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
12

13. Summary
Richer server programming model
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Any .NET framework language
Same mid - and server -tier data access:
midserverADO. NET
Same IDE, project model, debugging, tools
SQL Server hosting of .NET runtime
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Safety, security, scalability, speed
SQL Server .NET features
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Functions, stored procedures, triggers,
types, aggregates
Demos
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Sample code for function, stored procedure, and type
Assemblies
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Functions and stored procedures
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Safe versus external access
Creation and execution
Data access in-process via ADO .NET
in-
Types
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Type contract
Create type
Create table with column of user-defined type
userCreate index on column of user-defined type
userInsert and query the table
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
13

14. © 2001 Microsoft Corporation. All rights reserved.
PDC 2001
October 22-26, 2001
© 2001 Microsoft Corporation. All rights reserved.
14