Data and SQL Server 2014

Kenneth Ureña http://www.sqlcr.com @sqlcr

/SpanishPASSVC

Agenda

The journey of a transaction The Concurrency Issue - Hekaton Column Index Stored More New features

THE JOURNEY OF A TRANSACTION

Actual vacio

VirtualLogFile

Truncated

- Sequential Access- Just 1 file Active- Recommended

Raid 1 ó 1 + 0- Commit, backup log

trigger I/OLog

File

- Random Access- Multiple datafiles Active- Recommended Raid 1/1+0

5+0 / 5 - Checkpoint, backup, load /

unload Cache

Full Empty Full Empty

Empty Full Empty Full

Data Files

Cache fail

Loads page

Update page

CommitLazy Writter /

Checkpoint

Based on Dr. David Dewitt Key note

PASS Summit 2013 Charlotte

THE CONCURRENCY ISSUE

Serialized Scenario

T1 : A = A + 100 T2 : A = A + 500

T1 : Read A (0)

T1 Update A (100)T2 Read A (100) T2 Update A (600)

A = 600

Non-Serialized Scenario

T1 : A = A + 100 T2 : A = A + 500

T1 : Read A (0)

T1 Update A (100)

T2 Read A (0)

T2 Update A (500)

A = 500

Isolation Levels

Referencehttp://technet.microsoft.com/en-us/library/ms189122(v=sql.105).aspx

Isolation level Dirty read

Nonrepeatable read

Phantom

Read uncommitted

Yes Yes Yes

Read committed

No Yes Yes

Repeatable read

No No Yes

Snapshot No No No

Serializable No No No

In-Memory Demo• Database Creation• Native Stored Procedures• Mixed Stored Procedures• Isolation Levels

COLUMN INDEX STORE

Data access patterns

Seek Scan Bookmark Lookup

Column Index

Image fromhttp://magenic.com/

Column Index Store Demo• Database Creation• Queries comparison• New Features for column store

MORE NEW FEATURES

Resource Governor Improvements

Before 2014 Governor CPU per pool Governor Memory per pool

After 2014 Governor IOPS

Delayed durability

Return the control to the application before recording the data in the log area.

Buffer Pool Extension

It is like having an additional page file in windows but for SQL Server extending the buffer pool.

alter server configuration set buffer pool extension on (filename = 'C:\SQLServerDatabases\2014\BPCACHE\BufferPoolExtension.bpe‘, size = 20 GB);

AlwaysOn Enhancements

Maximum number of secondary replicas has been expanded from four to eight.

Readable secondary replicas are now also available for read workloads, even when the primary replica is unavailable

New Add Azure Replica Wizard, which helps you create asynchronous secondary replicas in Windows Azure

Q&A

Thank you

Kenneth Ureña http://www.sqlcr.com

@sqlcr

/SpanishPASSVC