Indexing

In-Memory OLTP (Hekaton), Licensing, Partitioning, SQL Server

A really odd choice I’ve talked a bit about my annoyance with hardware limits for Standard Edition here and here. If you’re a bunch of SQL-savvy developers who understand the Enterprise Edition features that are now available in 2016 SP1, great. You’re a very small minority of shops. I’m talking about places like StackOverflow and…

Top 5 Overlooked Index Features

Last Updated February 13, 2017

I see a lot of indexes Most of them are pretty vanilla. Some are pretty memorable, like one that I saw with 93 INCLUDES. A lot of things that people could do with indexes get overlooked, either because they don’t know about them, or they’re not sure when they’ll help. So, here goes my attempt…

Can Indexes My Query Doesn’t Use Help My Query?

Last Updated February 13, 2017

This came up during Office Hours And I love questions like this, because they reveal some interesting underpinnings of how the cardinality estimator works. It was something along the lines of “I have a slow query, and when I add an index the query goes faster even though it doesn’t use the index I created.”…

Partitioned Views: A How-To Guide

Last Updated February 13, 2017

Indexing, Partitioning, SQL Server

This is not about table partitioning If you want to learn about that, there’s a whole great list of links here, and the Best Blogger Alive has a tremendous post on why table partitioning won’t make your queries any faster over here. With that out of the way, let’s talk about partitioned views, and then…

Bad Idea Jeans Week: Dynamically Generating 999 Indexes on a Table

Last Updated February 13, 2017

Brent Ozar

Bad Idea Jeans, Humor, Indexing, SQL Server

Let’s say, just theoretically, you wanted to demo a query that takes SQL Server a long time to compile. And in order to make SQL Server’s job tougher, you wanted to create the maximum number of indexes possible on a table. You might do something like this: Transact-SQL SELECT TOP 999 'CREATE INDEX [IX_' +…

How To Fix Forwarded Records

Last Updated May 4, 2020

Tara Kizer

Some of our clients have very high forwarded record counts and aren’t aware of it until they run sp_BlitzFirst and get an alert about high Forwarded Records per Second. Some of these clients are using Ola Hallengren‘s IndexOptimize stored procedure to maintain their indexes. This brought up a question of whether or not rebuilding a…

Where Do Missing Index Requests Come From?

Last Updated November 16, 2017

Indexing, sp_BlitzIndex

Be honest, here You don’t care about most indexing problems. Duplicates, Borderline Duplicates, Unused, Wide, Non-aligned Partitions… All you’re here for are the Missing Indexes. Wham, bam, your query finishes in less than a second, ma’am. Take this quarter, go downtown and have a rat gnaw that thing off your face. And I get it.…

Why Not Just Create Statistics?

Last Updated February 13, 2017

Indexing, SQL Server, Statistics

Here at Brent Ozar Unlimited We have a proud tradition of not blaming index fragmentation for everything. There are points you should deal with it, but they’re probably not 5% and 30% and 1000 pages. But that’s not what this blog post is about. I’m hoping to clarify why we’re more interested in up to…

Spring Cleaning Your Databases

Last Updated February 13, 2017

Tara Kizer

Even with lots of monitoring in place, we should perform periodic checks of our SQL Servers. Think of this like “Spring Cleaning”, except I would recommend that it be more frequently than just once a year. Doing it monthly might be a bit ambitious due to our busy schedules, but quarterly could be achievable. Below are…

Temporal Tables, Partitioning, and ColumnStore Indexes

Last Updated February 13, 2017

Indexing, Partitioning, SQL Server

This post is mostly a thought experiment The thought was something along the lines of: I have a table I want to keep temporal history of. I don’t plan on keeping a lot of data in that table, but the history table can accumulate quite a bit of data. I want to partition the history…

Stats Week: Only Updating Statistics With Ola Hallengren’s Scripts

Last Updated June 17, 2017

Index Maintenance, Ola Hallengren's Database Maintenance Scripts

I hate rebuilding indexes There. I said it. It’s not fun. I don’t care all that much for reorgs, either. They’re less intrusive, but man, that LOB compaction stuff can really be time consuming. What I do like is updating statistics. Doing that can be the kick in the bad plan pants that you need…

Indexes Helping Indexes

Last Updated February 13, 2017

This post isn’t going to solve any problems for you It was just something I stumbled on that struck me as funny, while working on a demo for something else. Brent didn’t believe it at first, so I thought I’d share with the class. Blog. You, Your Name Here. Hiya! So there I was, creating…

Why most of you should leave Auto-Update Statistics on

Last Updated February 13, 2017

Index Maintenance, SQL Server, Statistics

Oh God, he’s talking about statistics again Yeah, but this should be less annoying than the other times. And much shorter. You see, I hear grousing. Updating statistics was bringin’ us down, man. Harshing our mellow. The statistics would just update, man, and it would take like… Forever, man. Man. But no one would actually…

Unique Indexes and Row Modifications: Weird

Last Updated March 12, 2018

Confession time This started off with me reading a blurb in the release notes about SQL Server 2016 CTP 3.3. The blurb in question is about statistics. They’re so cool! Do they get fragmented? NO! Stop trying to defragment them, you little monkey. Autostats improvements in CTP 3.3 Previously, statistics were automatically recalculated when the…

Should I Worry About Index Fragmentation?

Last Updated February 13, 2017

Doug Lane

Here’s a handy flowchart for whenever you find yourself worrying about fragmentation: *Talk to your doctor about whether fragmentation is a problem for you. Seek help for index maintenance lasting longer than four hours. Serious side effects may occur if all index maintenance is ignored completely. Brent says: pop quiz: what are you doing more…

Does index fill factor affect fragmentation?

Last Updated March 12, 2018

Everybody wants to know about index fragmentation It is an inescapable vortex of malaise and confusion. Like that swamp in The Neverending Story that killed the horse. Sorry if you haven’t seen that movie. The horse wasn’t that cool, anyway. Neither is index fragmentation, but it’s not worth losing sleep over. Or a horse. I…

Filtered Indexes: Just Add Includes

Last Updated May 9, 2018

I found a quirky thing recently While playing with filtered indexes, I noticed something odd. By ‘playing with’ I mean ‘calling them horrible names’ and ‘admiring the way other platforms implemented them‘. I sort of wrote about a similar topic in discussing indexing for windowing functions. It turns out that a recent annoyance could also…

Trace Flag 2330: Who needs missing index requests?

Last Updated February 13, 2017