MongoDB: The Definitive Guide: Powerful and Scalable Data Storage

216 Pages·2010·4.105 MB·English

by  Kristina Chodorow, Michael Dirolf

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MongoDB: The Definitive Guide
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MongoDB: The Definitive Guide
Kristina Chodorow and Michael Dirolf
Beijing • Cambridge • Farnham • Köln • Sebastopol • Tokyo
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MongoDB: The Definitive Guide
by Kristina Chodorow and Michael Dirolf
Copyright © 2010 Kristina Chodorow and Michael Dirolf. All rights reserved.
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Printing History:
September 2010: First Edition.
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tained herein.
ISBN: 978-1-449-38156-1
[M]
1283534198
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Table of Contents
Foreword ................................................................... xi
Preface .................................................................... xiii
1. Introduction ........................................................... 1
A Rich Data Model 1
Easy Scaling 2
Tons of Features… 2
…Without Sacrificing Speed 3
Simple Administration 3
But Wait, That’s Not All… 4
2. Getting Started ......................................................... 5
Documents 5
Collections 7
Schema-Free 7
Naming 8
Databases 8
Getting and Starting MongoDB 10
MongoDB Shell 11
Running the Shell 11
A MongoDB Client 12
Basic Operations with the Shell 12
Tips for Using the Shell 14
Data Types 15
Basic Data Types 16
Numbers 18
Dates 19
Arrays 19
Embedded Documents 20
_id and ObjectIds 20
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3. Creating, Updating, and Deleting Documents ............................... 23
Inserting and Saving Documents 23
Batch Insert 23
Inserts: Internals and Implications 24
Removing Documents 25
Remove Speed 25
Updating Documents 26
Document Replacement 26
Using Modifiers 27
Upserts 36
Updating Multiple Documents 38
Returning Updated Documents 39
The Fastest Write This Side of Mississippi 41
Safe Operations 42
Catching “Normal” Errors 43
Requests and Connections 43
4. Querying ............................................................. 45
Introduction to find 45
Specifying Which Keys to Return 46
Limitations 47
Query Criteria 47
Query Conditionals 47
OR Queries 48
$not 49
Rules for Conditionals 49
Type-Specific Queries 49
null 49
Regular Expressions 50
Querying Arrays 51
Querying on Embedded Documents 53
$where Queries 55
Cursors 56
Limits, Skips, and Sorts 57
Avoiding Large Skips 58
Advanced Query Options 60
Getting Consistent Results 61
Cursor Internals 63
5. Indexing ............................................................. 65
Introduction to Indexing 65
Scaling Indexes 68
Indexing Keys in Embedded Documents 68
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Indexing for Sorts 69
Uniquely Identifying Indexes 69
Unique Indexes 69
Dropping Duplicates 70
Compound Unique Indexes 70
Using explain and hint 70
Index Administration 75
Changing Indexes 76
Geospatial Indexing 77
Compound Geospatial Indexes 78
The Earth Is Not a 2D Plane 79
6. Aggregation .......................................................... 81
count 81
distinct 81
group 82
Using a Finalizer 84
Using a Function as a Key 86
MapReduce 86
Example 1: Finding All Keys in a Collection 87
Example 2: Categorizing Web Pages 89
MongoDB and MapReduce 90
7. Advanced Topics ....................................................... 93
Database Commands 93
How Commands Work 94
Command Reference 95
Capped Collections 97
Properties and Use Cases 98
Creating Capped Collections 99
Sorting Au Naturel 99
Tailable Cursors 101
GridFS: Storing Files 101
Getting Started with GridFS: mongofiles 102
Working with GridFS from the MongoDB Drivers 102
Under the Hood 103
Server-Side Scripting 104
db.eval 104
Stored JavaScript 105
Security 106
Database References 107
What Is a DBRef? 107
Example Schema 107
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Driver Support for DBRefs 108
When Should DBRefs Be Used? 108
8. Administration ....................................................... 111
Starting and Stopping MongoDB 111
Starting from the Command Line 112
File-Based Configuration 113
Stopping MongoDB 114
Monitoring 114
Using the Admin Interface 115
serverStatus 116
mongostat 118
Third-Party Plug-Ins 118
Security and Authentication 118
Authentication Basics 118
How Authentication Works 120
Other Security Considerations 121
Backup and Repair 121
Data File Backup 121
mongodump and mongorestore 122
fsync and Lock 123
Slave Backups 124
Repair 124
9. Replication .......................................................... 127
Master-Slave Replication 127
Options 128
Adding and Removing Sources 129
Replica Sets 130
Initializing a Set 132
Nodes in a Replica Set 133
Failover and Primary Election 135
Performing Operations on a Slave 136
Read Scaling 137
Using Slaves for Data Processing 137
How It Works 138
The Oplog 138
Syncing 139
Replication State and the Local Database 139
Blocking for Replication 140
Administration 141
Diagnostics 141
Changing the Oplog Size 141
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