1. SQL Server 2008 T-SQL Enhancements SELECT TOP(10) t_sql_enhancements
FROM SQLServer2008
ORDER BY CHECKSUM(NEWID());
Plamen Ratchev
Tangra, Inc.

2. Quiz How many new T-SQL features do you see?
INT = (SELECT MAX(customer_nbr) FROM Customers);
+= 1;
INSERT INTO Customers
VALUES 'John Doe'), + 1, 'Jane Fisher');
VALUES ((SELECT MAX(customer_nbr) + 1 FROM Customers), 'Jeff Brown');

3. Quiz Would this SQL statement run?
INSERT INTO LoansHistory (loan_nbr, loan_amount, loan_date)
SELECT loan_nbr, loan_amount, loan_date
FROM (DELETE Loans
OUTPUT deleted.loan_nbr,
deleted.loan_amount,
deleted.loan_date
WHERE loan_date < ' ') AS L;

4. Agenda Delighters Row constructors MERGE Composable DML
Table valued parameters
Filtered indexes
Sparse columns
Hierarchy ID
Date and Time data types
FILESTREAM data type

5. Delighters Inline variable initialization and compound assignment
INT = 1;
+= 1;
/= 2;
*= 5;
%= 3;
-= 1;
UPDATE PayRates
SET pay_rate *= performance_score * 0.25;
DECIMAL(15, 2) = (SELECT MAX(pay_rate)
FROM PayRates);

6. Row constructors -- Insert data using row constructors
INSERT INTO Employees (employee_nbr, employee_name)
VALUES (1, 'Jim Smith'),
(2, 'Joe Doe'),
(3, 'Greg Brown'),
(4, 'Donna Ford');
-- Inline table expression
SELECT employee_nbr, employee_name
FROM (VALUES (1, 'Jim Smith'),
(4, 'Donna Ford')
) AS E(employee_nbr, employee_name);

7. MERGE Statement Definition
The MERGE syntax consists of four primary clauses:
The MERGE clause specifies the table or view that is the target of the INSERT, UPDATE, or DELETE operations.
The USING clause specifies the data source being joined with the target.
The ON clause specifies the join conditions to determine where the target and source match.
The WHEN clauses specify the actions to take based on the results of the ON clause.

8. MERGE Statement Syntax
[ WITH <common_table_expression> [,...n] ]
MERGE
[ TOP ( expression ) [ PERCENT ] ]
[ INTO ] target_table [ [ AS ] table_alias ]
[ WITH ( <merge_hint> ) ]
USING <table_source>
ON <search_condition>
[ WHEN MATCHED [ AND <search_condition> ]
THEN <merge_matched> ]
[ WHEN [TARGET] NOT MATCHED [ AND <search_condition> ]
THEN <merge_not_matched> ]
[ WHEN SOURCE NOT MATCHED [ AND <search_condition> ]
THEN <merge_ matched> ]
<output_clause>
[ OPTION ( <query_hint> [ ,...n ] ) ] ;

9. MERGE Statement Example: Update existing and add missing
MERGE INTO CentralOfficeAccounts AS C -- Target
USING BranchOfficeAccounts AS B -- Source
ON C.account_nbr = B.account_nbr
WHEN MATCHED THEN On match update
UPDATE SET C.company_name = B.company_name,
C.primary_contact = B.primary_contact,
C.contact_phone = B.contact_phone
WHEN NOT MATCHED THEN -- Add missing
INSERT (account_nbr, company_name, primary_contact, contact_phone)
VALUES (B.account_nbr, B.company_name, B.primary_contact, B.contact_phone);

10. MERGE Statement Example: Update existing that changed and add missing
MERGE INTO CentralOfficeAccounts AS C -- Target
USING BranchOfficeAccounts AS B -- Source
ON C.account_nbr = B.account_nbr
WHEN MATCHED On match update
AND (C.company_name <> B.company_name -- Additional search conditions
OR C.primary_contact <> B.primary_contact
OR C.contact_phone = B.contact_phone) THEN UPDATE SET C.company_name = B.company_name,
C.primary_contact = B.primary_contact,
C.contact_phone = B.contact_phone
WHEN NOT MATCHED THEN -- Add missing
INSERT (account_nbr, company_name, primary_contact, contact_phone)
VALUES (B.account_nbr, B.company_name, B.primary_contact, B.contact_phone);

11. MERGE Statement Example: Update existing that changed and add missing, delete missing in source
MERGE INTO CentralOfficeAccounts AS C -- Target
USING BranchOfficeAccounts AS B -- Source
ON C.account_nbr = B.account_nbr
WHEN MATCHED On match update
AND (C.company_name <> B.company_name
OR C.primary_contact <> B.primary_contact
OR C.contact_phone = B.contact_phone) THEN UPDATE SET C.company_name = B.company_name,
C.primary_contact = B.primary_contact,
C.contact_phone = B.contact_phone
WHEN NOT MATCHED THEN -- Add missing
INSERT (account_nbr, company_name, primary_contact, contact_phone)
VALUES (B.account_nbr, B.company_name, B.primary_contact, B.contact_phone)
WHEN SOURCE NOT MATCHED THEN -- Delete missing from source
DELETE;

12. Composable DML INSERT INTO AccountsAudit
(account_nbr, change_action, old_company_name, new_company_name)
SELECT account_nbr, merge_action, old_company_name, new_company_name
FROM (MERGE INTO CentralOfficeAccounts AS C
USING BranchOfficeAccounts AS B
ON C.account_nbr = B.account_nbr
WHEN MATCHED
AND C.company_name <> B.company_name THEN
UPDATE SET C.company_name = B.company_name
WHEN NOT MATCHED THEN
INSERT (account_nbr, company_name,
primary_contact, contact_phone)
VALUES (B.account_nbr, B.company_name,
B.primary_contact, B.contact_phone)
WHEN SOURCE NOT MATCHED THEN
DELETE
OUTPUT $action,
COALESCE(inserted.account_nbr, deleted.account_nbr),
deleted.company_name,
inserted.company_name
) AS T(merge_action, account_nbr, old_company_name, new_company_name);

13. Table valued parameters
-- User-defined table type
CREATE TYPE LoanTable
AS TABLE (
loan_nbr INT PRIMARY KEY,
loan_date DATETIME,
loan_amount DECIMAL(15, 2));
-- Procedure with table valued parameter
-- Must use the READONLY clause
CREATE PROCEDURE InsertLoans
@Loans LoanTable READONLY AS
INSERT INTO Loans
SELECT loan_nbr, loan_date, loan_amount
-- Declare table variable of the new type
LoanTable;
-- Insert new loans using the table variable as parameter
EXEC

14. Table valued parameters Client side ADO. NET (v3
Table valued parameters Client side ADO.NET (v3.5) support for table valued parameters
DataTable loans;
loans = new DataTable();
loans.Columns.Add("loan_nbr", typeof(int));
loans.Columns.Add("loan_date", typeof(System.DateTime));
loans.Columns.Add("loan_amount", typeof(decimal));
using(SqlCommand cmd = new SqlCommand("InsertLoans", conn) {
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("Loans", loans);
cmd.ExecuteNonQuery(); }

15. Filtered indexes CREATE NONCLUSTERED INDEX ix_SouthEastRegion
ON Regions (region_cd)
INCLUDE(region_name, region_phone)
WHERE region_cd = 'SE';
SELECT region_cd, region_name, region_phone
FROM Regions
WHERE region_cd = 'SE';
SELECT region_cd, region_name, region_phone
FROM Regions
WHERE region_cd = ‘NE';

16. Filtered indexes -- Guarantee unique values excuding NULLs
CREATE UNIQUE NONCLUSTERED INDEX ix_RegionPhone
ON Regions (region_phone)
WHERE region_phone IS NOT NULL;
-- OK
INSERT INTO Regions VALUES ('NW', 'North West', NULL);
-- Error:
-- Cannot insert duplicate key row in object 'dbo.Regions'
-- with unique index 'ix_RegionPhone‘.
INSERT INTO Regions VALUES ('NW', 'North West', ' ');

17. Sparse columns
Pros:
Storing NULL in a sparse column takes up no space at all
Up to 30,000 columns
To any external application the column will behave the same
Sparse columns fit well with filtered indexes to index on non-empty values
Cons:
If a sparse column has data it takes 4 more bytes than a normal column
Not all data types can be sparse: TEXT, NTEXT, IMAGE, TIMESTAMP, user-defined data types, GEOMETRY, GEOGRAPHY, and VARBINARY(MAX) with the FILESTREAM attribute
Computed columns cannot be sparse
Cannot have default values

18. Sparse columns CREATE TABLE Survey (
survey_nbr INT NOT NULL PRIMARY KEY,
survey_desc VARCHAR(30),
survey_info1 VARCHAR(30) SPARSE NULL,
survey_info2 VARCHAR(30) SPARSE NULL,
survey_info3 VARCHAR(30) SPARSE NULL,
survey_info4 VARCHAR(30) SPARSE NULL);
INSERT INTO Survey(survey_nbr, survey_desc, survey_info1)
VALUES(1, 'Survey 1', 'some data'),
(2, 'Survey 2', 'good');

19. Sparse columns Column sets
CREATE TABLE Survey (
survey_nbr INT NOT NULL PRIMARY KEY,
survey_desc VARCHAR(30),
survey_info1 VARCHAR(30) SPARSE NULL,
survey_info2 VARCHAR(30) SPARSE NULL,
survey_info3 VARCHAR(30) SPARSE NULL,
survey_info4 VARCHAR(30) SPARSE NULL,
survey_set XML column_set FOR ALL_SPARSE_COLUMNS);
INSERT INTO Survey(survey_nbr, survey_desc, survey_set)
VALUES(3, 'Survey 3',
'<survey_info3>data 3</survey_info3>
<survey_info4>answer 4</survey_info4>');
Defined as XML data type column
Not stored, like computed column, but updatable
Only one column set per table
Cannot be changed
Cannot be added if the table already has sparse columns
Limited by XML data size limit of 2 GB (all sparse columns in a row cannot exceed 2 GB)
Cannot define constraints or default values
Allows to update or insert sparse column values
On update all sparse columns are updated, when no value provided sets the column to NULL

20. Graphs and Trees with HIERARCHYID
Compact storage
Convenient methods for nodes manipulation
Single root
Does not automatically represent a tree; application has to define relationships
Application needs to manage consistency

21. Graphs and Trees with HIERARCHYID
CREATE TABLE Employees (
emp_id INT NOT NULL PRIMARY KEY,
emp_name VARCHAR(35),
manager_id INT REFERENCES Employees(emp_id),
org_chart_path HIERARCHYID);
-- Insert the top level manager as hierarchy root
INSERT INTO Employees
VALUES (1, 'Jeff Brown', NULL, hierarchyid::GetRoot());
-- Insert John who reports to the top level manager
VALUES (2, 'John Doe', 1,
(SELECT hierarchyid::GetRoot().GetDescendant(NULL, NULL)
FROM Employees));

22. Graphs and Trees with HIERARCHYID
-- Insert Peter at the same level as John
HIERARCHYID = (SELECT org_chart_path
FROM Employees
WHERE emp_name = 'John Doe');
INSERT INTO Employees
VALUES (3, 'Peter Hanna', 1,
(SELECT NULL)
WHERE org_chart_path = hierarchyid::GetRoot()));
-- Insert Richard as reporting to John
VALUES (4, 'Richard Burns', 2,
hierarchyid::Parse('/1/1/')); -- Also: CAST('/1/1/' AS HIERARCHYID)
SELECT emp_id, emp_name,
manager_id, org_chart_path,
org_chart_path.GetAncestor(1) AS emp_manager,
hierarchyid::GetRoot() AS top_manager,
org_chart_path.GetDescendant(NULL, NULL) AS emp_descendant,
org_chart_path.GetLevel() AS emp_level,
org_chart_path.ToString() AS emp_org_path
FROM Employees;

23. Graphs and Trees with HIERARCHYID
-- Move Richard to report to Peter
HIERARCHYID = (SELECT org_chart_path
FROM Employees
WHERE emp_name = 'Peter Hanna');
UPDATE Employees
SET org_chart_path = org_chart_path.Reparent(org_chart_path.GetAncestor(1),
@new_mgr)
WHERE emp_name = 'Richard Burns';

24. Date and Time data types
DATE ( through )
TIME (00:00: through 23:59: )
DATETIME2 (fraction 0 through 7)
DATETIMEOFFSET (time zone awareness)
Functions:
SYSDATETIME
SYSDATETIMEOFFSET
SYSUTCDATETIME
SWITCHOFFSET
TODATETIMEOFFSET

25. FILESTREAM data type Implemented as VARBINARY(MAX)
No limitation of 2 GB
Stored in the file system
Fast read access
Good for objects larger then ~ MB
Encryption is not supported
Setting to NULL deletes the BLOB data
Transactional consistency
Windows access via the OpenSqlFilestream APIs (read/write; no delete or rename)
Uses Windows cache not using SQL Server buffer pool, more memory for queries
A ROWGUIDCOL column is required to use FILESTREAM data with Win32 APIs

26. FILESTREAM data type Enabling FILESTREAM EXEC sp_filestream_configure
Levels:
0 - Disabled. This is the default value
1 - Enabled only for Transact-SQL access
2 - Enabled only for Transact-SQL and local file system access.
3 - Enabled for Transact-SQL, local file system access, and remote file system access.
Create database supporting FILESTREAM and table with FILESTREAM column
EXEC sp_filestream_configure
@enable_level = 3,
@share_name = "FileStreamShare";
CREATE DATABASE BlobDatabase ON PRIMARY
( NAME = Blob,
FILENAME = 'C:\Data\Blob.mdf'),
FILEGROUP FSGroup CONTAINS FILESTREAM
( NAME = BlobFS,
FILENAME = 'C:\Data\FileStream')
LOG ON ( NAME = BlobLog,
FILENAME = 'C:\Data\Blob.ldf');
CREATE TABLE BlobDatabase.dbo.Images (
image_id UNIQUEIDENTIFIER
ROWGUIDCOL NOT NULL UNIQUE,
image_desc VARCHAR(35),
image_data VARBINARY(MAX)
FILESTREAM NULL);

27. What else? New data types Spatial data (GEOMETRY and GEOGRAPHY)
Grouping Sets
Function changes
Table hints (FORCESEEK)
Star join query optimizations
T-SQL debugger is back