CouchDB is an open-source, NoSQL database that is designed for scalability, fault-tolerance, and ease of use. It is a document-oriented database that stores data in JSON format and allows users to query and manipulate it using JavaScript or other languages.
Audience
This CouchDB tutorial is designed to help beginners learn the basics of installing, configuring, and using this powerful NoSQL database. We will cover topics such as setting up your environment, creating databases, manipulating data, and replicating databases. By the end of this tutorial, you will have a basic understanding of CouchDB and be able to begin developing applications with it.
Prerequisites
1. Basic knowledge of databases and document-oriented databases
2. Understanding of web technologies such as HTML and JavaScript
3. Experience using a command-line interface
4. Basic understanding of JSON data structures
5. Working knowledge of programming languages such as Python or JavaScript
CouchDB – Introduction
CouchDB is an open-source, document-oriented NoSQL database. It stores data in JSON documents and enables users to query and manipulate the data using JavaScript. It is designed for scalability and replication, making it a great choice for distributed systems. It also provides an easy-to-use RESTful interface, allowing for easy integration with other systems. CouchDB is highly available, secure, and highly performant. It can be used to store and manage data for web and mobile applications, IoT, Big Data, and more.
RDBMS
RDBMS stands for Relational Database Management System. It is a type of database management system (DBMS) that stores data in the form of related tables. It uses Structured Query Language (SQL) for defining and manipulating data. It is the most popular type of DBMS and is used in a variety of applications.
OLAP
An OLAP cube is an analytics tool used to analyze data from multiple perspectives. It is a multi-dimensional database that is organized in a cube structure and allows users to quickly and easily access data from multiple angles and dimensions. OLAP cubes are commonly used in data warehouses and business intelligence applications to help analyze large datasets and uncover meaningful insights.
NoSQL Databases
NoSQL databases are non-relational databases that store data in a flexible format, allowing for scalability and rapid development. It can store data in a variety of formats including key-value pairs, documents, graphs, and columns. NoSQL databases are used for applications that require high throughput, scalability, and flexibility, such as web and mobile applications. Some popular NoSQL databases include MongoDB, Apache Cassandra, and Voldemort.
The primary objective of a NoSQL database is to have the following features:
1. High scalability: NoSQL databases are designed to be easily and quickly scalable, allowing them to quickly accommodate large amounts of data and high levels of user activity.
2. High availability: NoSQL databases are designed to be resilient against outages, ensuring that data can be accessed and stored reliably.
3. Flexible data models: NoSQL databases are not bound by the rigid structure of relational databases, allowing them to store and organize data in a variety of formats.
4. High performance: NoSQL databases are designed to be able to quickly process large amounts of data and respond in real-time.
5. Low cost: NoSQL databases are typically open-source and less expensive to operate than traditional relational databases.
What is CouchDB
CouchDB is an open source NoSQL document-oriented database system. It is written in the Erlang programming language and uses JSON, JavaScript, and HTML for data storage. CouchDB uses a concept called “multi-version concurrency control” to provide concurrent access to data without the need for locking. It also provides an API for creating, retrieving, updating, and deleting documents, as well as an HTTP-based query language. CouchDB is designed to be highly available and partition tolerant, meaning it can handle outages and still remain available.
Why CouchDB?
CouchDB is a popular open source NoSQL database that is designed for ease of use and scalability. It is a document-oriented database, which means it stores data in the form of documents, rather than as tables with rows and columns. This makes it easier to work with and modify data, as documents can be easily updated and modified. CouchDB is also highly scalable, as it is designed to be used in distributed environments. It is also highly reliable, as it uses a model of eventual consistency, which ensures that all replicas of the data remain in sync. CouchDB is a great choice for applications that require high levels of scalability, availability, and data flexibility.
Data Model
CouchDB data models are based on documents, which are collections of key-value pairs. The documents are stored in a JSON format and are linked together using a unique identifier called a “_id”. Documents can be linked together using “_rev”, which is a revision identifier. This allows for efficient data storage, retrieval, and updates. Documents can also be indexed using “views”, which are stored as JavaScript functions. Views are used to query and filter data, and can be used to create reports and other information. CouchDB also provides a built-in query language called “MapReduce”, which is used to build complex queries from simple ones.
Features of CouchDB:Reduce the Content Management System
• CouchDB is an open source database that allows users to store and manage data easily.
• It can scale from a single server to a large distributed system.
• CouchDB is written in Erlang, a high-performance language that is ideal for distributed systems.
• CouchDB has a document-oriented data model which is more flexible than the traditional relational model.
• It has a powerful query language that allows users to query the data in the database quickly and efficiently.
• CouchDB is designed to be highly available and fault tolerant, so it can cope with system failures and data corruption.
• It also supports replication, so that data can be synchronized across multiple servers.
• CouchDB is easy to set up and manage, and it has powerful features such as map-reduce views, change notifications, and document validation.
ACID Properties
CouchDB contains ACID properties as one of its features. ACID stands for Atomicity, Consistency, Isolation, and Durability. These properties ensure that data is kept consistent and correct even when multiple users are accessing it. Atomicity requires that all operations within a transaction must complete successfully or none of them will apply. Consistency ensures that the data remains valid after a transaction is complete. Isolation ensures that transactions do not interfere with each other. Durability ensures that the data is not lost even if there is an interruption, such as a power failure.
Compaction
Compaction is an important process in ACID compliance. It helps to reduce the storage space required for the data and improve the performance of the database. Compaction works by merging multiple records with the same key into one record, which reduces the number of records and reduces the storage space required. Compaction also helps to ensure ACID compliance, as it reduces the number of records that need to be modified when a transaction occurs, which helps to reduce the risk of data inconsistency.
Views
CouchDB views are JavaScript functions stored in the database that allow for the querying and joining of documents. The view functions are written using the MapReduce programming model and can be used to generate lists of documents, key/value pairs, or convert data into a specific format. Views are indexed and stored in the database, which makes them efficient to query and retrieve data. Views are used to query data, filter data, and group documents. They provide an easy way to query data, and they can be used to create reports and charts.
History
CouchDB was created in 2005 by Damien Katz while working at IBM. It was initially released in 2008 by Apache Software Foundation and was written in the Erlang programming language. The database was designed to be used for web applications and is based on the document-oriented NoSQL database model. CouchDB is a distributed database, meaning that it stores data across multiple servers and allows for high scalability and performance. It is also known for its replication features, which allow data to be synchronized across multiple nodes. CouchDB also provides support for MapReduce and other ways of querying data. Over the years, CouchDB has been widely adopted for its flexibility and scalability, and is used by many large companies including Facebook, Twitter, and LinkedIn.
CouchDB – Installation
CouchDB is an open-source, document-oriented NoSQL database. It is written in the Erlang programming language.
Installing CouchDB on Windows:
1. Download the latest version of CouchDB from the official website.
2. Run the downloaded executable file to begin the installation process.
3. Select a directory to install CouchDB.
4. Accept the license agreement and click “Next”.
5. Select the components you want to install and click “Next”.
6. Click “Install” to begin the installation process.
7. Once the installation is complete, click “Finish”.
Installing CouchDB on Mac
1. Download the latest version of CouchDB from the official website.
2. Unzip the downloaded file and copy the CouchDB folder to the Applications folder.
3. Launch the CouchDB application.
4. Accept the license agreement and click “Continue”.
5. Select the components you want to install and click “Continue”.
6. Click “Install” to begin the installation process.
7. Once the installation is complete, click “Done”.
Installing CouchDB
1. Download the CouchDB package from the official website: https://couchdb.apache.org/#download
2. Unzip the package and move it to the location you want to install CouchDB to.
3. Run the installation file to begin the installation process.
4. Follow the instructions in the installation wizard to complete the setup.
5. Once the installation is complete, you can launch CouchDB from the Start Menu.
6. You can access the CouchDB administrative interface by navigating to http://127.0.0.1:5984/_utils/ in your web browser.
Installing CouchDB in Linux Systems
1. Download the latest version of CouchDB for Linux systems from the CouchDB website.
2. Extract the archive to the desired location.
3. Change to the CouchDB directory: cd couchdb
4. Install the prerequisites: sudo apt-get install build-essential erlang libicu-dev libmozjs185-dev libcurl4-openssl-dev
5. Compile and install CouchDB: ./configure && make && sudo make install
6. Create the CouchDB user and group: sudo adduser –disabled-login –disabled-password –no-create-home –gecos “CouchDB Administrator” couchd
7. Change the ownership of the CouchDB directories: sudo chown -R couchdb:couchdb /usr/local/var/lib/couchdb /usr/local/var/log/couchdb /usr/local/var/run/couchdb
8. Start CouchDB: sudo -i -u couchdb /usr/local/bin/couchd
9. Check the status of CouchDB: sudo /etc/init.d/couchdb status
10. Configure CouchDB to start automatically when the system boots: sudo update-rc.d couchdb defaults
Installing CouchDB Dependencies
In order to install the necessary dependencies for CouchDB, you will need to have access to a package manager, such as apt-get or yum. From there, you can use the package manager to install the necessary packages, such as Erlang, SpiderMonkey, and OpenSSL. Once the packages have been installed, you can then proceed to install CouchDB itself.
Downloading CouchDB
You can download the latest version of CouchDB from the Apache CouchDB official website. Once you have downloaded the CouchDB software, you can install it on your computer. The installation process is easy and straightforward, and you will be able to start using the software in no time.
Configuring CouchDB
1. Download CouchDB:
The first step to configure CouchDB is to download the software. You can download CouchDB from the official website or from any other reliable source.
2. Install CouchDB:
After downloading CouchDB, you need to install it. You can either choose to install it manually or use a package manager like apt-get or yum to install it.
3. Setup Admin Account:
After installing CouchDB, you need to setup an admin account. You can do this by running the couchdb command and following the instructions on the screen.
4. Configure Security Settings:
It is important to configure the security settings of CouchDB. This includes setting up authentication and authorization for users and databases.
5. Configure Database Replication:
Database replication is a powerful feature of CouchDB that allows you to replicate your data across multiple nodes. You can configure database replication by using the web interface or a command line tool.
6. Configure Backup and Restore:
It is important to configure backup and restore for your databases. You can configure automatic backups or manual backups depending on your preference.
7. Start CouchDB:
Once you have configured CouchDB, you can start the service. You can do this by running the couchdb command or by using the web interface.
Installing CouchDB
1. Download the CouchDB installer. Depending on your operating system, the installer package may be available from the official CouchDB website, from the Apache Software Foundation, or from a third-party source.
2. Double-click the installer package to launch the setup wizard. Follow the on-screen instructions to complete the installation process.
3. Once the installation is complete, launch the CouchDB service from the Windows Start menu.
4. Open the browser and visit http://localhost:5984/_utils to access the CouchDB dashboard.
5. Click on ‘Create Database’ to create a new database.
6. Enter the database name and click ‘Create’. The new database will be listed on the left-hand side.
7. To add documents to the database, click on the ‘Add Document’ button and enter the document data in JSON format.
8. To query the database, click on the ‘Query’ button and enter the query in the query box.
9. Click ‘Run Query’ to execute the query and view the results.
10. To access the database from another machine, open the CouchDB configuration file (couch.ini) and change the bind_address setting to the IP address of the machine. Save the configuration file and restart the CouchDB service.
Starting CouchDB
CouchDB can be started by typing the following command in terminal:
couchdb
This will start the CouchDB server.
CouchDB – Curl & Futon
Curl is a command line tool used to make HTTP requests. It is used for managing and manipulating CouchDB databases. Futon is an administrative web interface for CouchDB. It is used for creating and managing databases and documents.
cURL Utility
cURL is a command line tool and library for transferring data with URLs. It supports various protocols including HTTP, HTTPS, FTP, and many more. It is used for downloading and uploading files, posting data to web servers, testing web applications, and automating web activities. cURL is often used by developers to test web applications and APIs. It can also be used by system administrators to access and manage remote servers.
Using cURL Utility
cURL is a command-line tool used for transferring data with a URL syntax. It supports a wide variety of protocols, including HTTP, HTTPS, FTP, and SMTP. To download a file using cURL, the syntax would be the following:
curl -O <url>
For example, to download a file from example.com, the command would be:
curl -O http://www.example.com/filename.zip
cURL Utility Options
cURL is a command line utility for transferring data from or to a server. It supports a wide range of protocols such as HTTP, HTTPS, FTP, SFTP, IMAP, POP3, etc. It supports many useful options for accessing and manipulating remote data. These options include:
1. -u/–user: This option allows you to specify the user name and password to be used for server authentication.
2. -X/–request: This option allows you to specify the type of HTTP request to be made (e.g. GET, POST, etc.).
3. -I/–head: This option displays the response headers without the actual response body.
4. -d/–data: This option allows you to specify the data to be sent to the server in the HTTP request body.
5. -o/–output: This option allows you to write the response body to a file instead of displaying it in the terminal.
6. -H/–header: This option allows you to specify HTTP request headers.
7. -C/–continue-at: This option allows you to resume an interrupted download.
8. -T/–upload-file: This option allows you to upload a file to the server.
9. -v/–verbose: This option displays detailed information about the request and response.
10. -b/–cookie: This option allows you to send cookies with the request.
-X flag
The -X flag in cURL allows you to specify an arbitrary request method to use when communicating with the server. This can be used to send requests containing any HTTP verb, such as PUT or DELETE.
-H
To authenticate with HTTP-Basic-Authentication using cURL, use the `-u` flag.
“`
curl -u username:password <URL>
“`
-o flag
The -s or –silent flag can be used in cURL to make it silent.
-d flag
Using this flag of cURL command you can specify the contents of the data to be sent with a POST request.
Syntax:
curl -d [data] [URL]
Example:
curl -d “name=John&age=30” http://example.com/form.php
Hello CouchDB
CouchDB is a powerful database system that is known for its scalability, robustness, and availability. It is a great choice for applications that require high performance, scalability, and high availability. CouchDB is a great choice for web applications, mobile applications, and IoT applications.
List of All Databases
1. MySQL
2. MongoDB
3. Oracle
4. Microsoft SQL Server
5. PostgreSQL
6. IBM DB2
7. Amazon Redshift
8. Apache Cassandra
9. Firebase Realtime Database
10. Microsoft Access
11. IBM Informix
12. SQLite
13. Amazon Aurora
14. MariaDB
15. Apache HBase
16. MemSQL
17. Neo4j
18. CouchDB
Creating a Database
1. Start by opening your database software.
2. Select a suitable database type for your needs.
3. Create a new database by entering a name for the database and choosing a location.
4. Create tables to store the data you will be entering into the database.
5. Choose the appropriate data types for each column in the tables you created
6. Define the relationships between the tables.
7. Design an efficient indexing system to quickly retrieve data.
8. Design and create views to help you quickly and easily display information.
9. Create stored procedures and triggers to automate tasks and maintain data integrity.
10. Finally, test the database and make sure it meets your requirements.
Getting Database Info
To get database info, you can use a variety of methods. The most common methods involve connecting to the database server and running SQL queries to get information. You can also use the database management tools provided by the database vendor to access the database and view information. Additionally, some databases provide APIs that can be used to access and gather data from the database.
Futon
Futon CouchDB is an open source database platform based on the CouchDB database engine. It is designed to provide an easy-to-use, web-based interface for users to manage their databases. The platform is used for document-oriented storage, which means that documents are stored in a database as individual documents. It is designed for scalability, allowing users to store large amounts of data in a single database. It also provides support for multi-document transactions, which means that multiple documents can be changed in a single transaction. It also provides an API for creating and managing views, which allows users to query the data stored in their database.
Databases −
Futon databases are non-relational databases that are built on the Futon Couch framework. Futon databases are highly scalable and provide a simple and intuitive interface for creating, managing, and querying data. They are used for a variety of web and mobile applications, such as content management systems, e-commerce sites, and social networks. Futon databases are powerful, cost-effective, and highly efficient, allowing developers to create dynamic applications with minimal effort.
Documents −
Futon documents are documents that are created using the open source Futon web application development platform. Futon documents are typically used to create web applications and web services. They are written in XML and JavaScript and can be used to create complex web applications.
Starting Futon
Futon is a web-based interface for Apache CouchDB. It is available as a package for most Linux distributions, and is part of Apache CouchDB’s official releases. Futon provides a web-based graphical user interface to administer, configure, and manage Apache CouchDB databases and document stores. Through Futon, users can create, delete, and modify databases, and add and delete documents. Additionally, Futon provides users with an easy and intuitive way to view and modify the data stored in their databases.
CouchDB – HTTP API
CouchDB provides a RESTful interface for accessing and managing data stored in the database. The API allows developers to interact with the database directly via HTTP requests. It is designed to be simple and straightforward, and provides a wide range of features including document management, query support, version control, and replication. Additionally, CouchDB provides an event-based model for notifying clients of changes to the database.
HTTP Request Formats
1. GET: This request format is used to retrieve information from a server. It is typically used for non-destructive operations, such as requesting a web page.
2. POST: This request format is used to submit information to the server. It is usually used for destructive operations, such as submitting a form.
3. PUT: This request format is used to update a resource on the server. It is typically used for destructive operations, such as updating a database record.
4. DELETE: This request format is used to delete a resource on the server. It is typically used for destructive operations, such as deleting a database record.
HTTP Request Headers
The request headers are the HTTP headers sent from the browser to the server. These headers are used to communicate information about the request being made, such as the type of request (GET, POST, etc.), the content type, the user agent, cookies, the referrer, and other information. They are sent as an HTTP header named “Request” in the request message. Examples of request headers include:
Accept: text/html
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.122 Safari/537.36
Accept-Language: en-US
Accept-Encoding: gzip, deflate, br
Connection: keep-alive
Host: www.example.com
Response Headers
Cache-Control:private
Content-Encoding:gzip
Content-Type:text/html; charset=utf-8
Date:Mon, 22 Nov 2020 22:30:16 GMT
Transfer-Encoding:chunked
Vary:Accept-Encoding
X-AspNet-Version:4.0.30319
X-Powered-By:ASP.NET
Status Codes in CouchDB – HTTP API
200 OK – The request was successful.
201 Created – The request was successful and the resource was created.
202 Accepted – The request was accepted but not yet completed.
400 Bad Request – The request was incorrect or could not be processed.
401 Unauthorized – The request was not authorized.
403 Forbidden – The server is refusing to fulfill the request.
404 Not Found – The requested resource was not found.
409 Conflict – The request conflicts with the current state of the resource.
412 Precondition Failed – The request did not meet one or more of the preconditions specified.
500 Internal Server Error – The server encountered an unexpected error.
HTTP URL Paths in CouchDB – HTTP API
The CouchDB HTTP API provides access to the database and its documents, views, and related resources. The CouchDB HTTP API is exposed via an HTTP server.
The base URL for the CouchDB HTTP API is /. The following are the main paths used in the CouchDB HTTP API:
• /_all_dbs – Returns a list of all databases in the CouchDB instance
• /{db_name} – Returns information about the specified database
• /{db_name}/_all_docs – Returns a list of all documents in the specified database
• /{db_name}/_design/{design_doc_name} – Returns the design document for the specified database
• /{db_name}/_view/{view_name} – Returns the view for the specified database
• /{db_name}/{doc_id} – Returns the document with the specified document ID from the specified database
• /{db_name}/_changes – Returns changes to documents in the specified database
• /_session – Returns information about the current session
• /_uuids – Returns a list of UUIDs for use in document IDs
• /_active_tasks – Returns a list of active tasks in the CouchDB instance
• /_replicate – Starts or stops replications of databases
• /_stats – Returns statistical information about the CouchDB instance
• /_config – Returns information about the configuration of the CouchDB instance
• /_restart – Restarts the CouchDB instance
CouchDB – Creating a Database
1. Open the CouchDB web interface by navigating to http://localhost:5984/_utils/ in your web browser
2. Click on the “Create Database” link in the top-right corner of the page.
3. Enter the name for your new database in the text box and click “Create”.
4. Congratulations! Your new database is now ready to use.
Creating a Database using cURL Utility
1. Log into your server via SSH
2. Create a new database by entering the following command:
CREATE DATABASE database_name;
3. Create a new user with the following command:
CREATE USER ‘username’@’localhost’ IDENTIFIED BY ‘password’;
4. Grant the user access to the newly created database by entering the following command:
GRANT ALL PRIVILEGES ON database_name.* TO ‘username’@’localhost’;
5. Flush the privileges by entering the following command:
FLUSH PRIVILEGES;
6. Now you can use cURL to create tables in the newly created database. Enter the following command in order to do so:
curl -X POST -u username:password –data “query=CREATE TABLE table_name (column_1 datatype, column_2 datatype, … )” http://localhost/query
7. Finally, you can check if the table has been created successfully by entering the following command:
SELECT * FROM table_name;
Creating a Database using Futon
1. Log in to Futon by entering the URL http://127.0.0.1:5984/_utils/ in your browser.
2. Click on the ‘Create Database’ button on the top-right corner.
3. Enter a name for your new database in the given field and click ‘Create’.
4. You will now see a confirmation message saying the database was created.
5. To view the database in Futon, click on the database name in the left pane. Here you will see a list of documents and views associated with the database.
6. To add documents or create views, click on the relevant option in the left pane.
CouchDB – Deleting a Database
1. Log into the CouchDB admin panel.
2. Click on the “Databases” tab.
3. Select the database you wish to delete.
4. Click the “Delete Database” button.
5. Confirm the deletion by clicking “Delete” in the confirmation dialog.
CouchDB – Creating a Document
To add a document to CouchDB, you can use the curl command line utility or one of the available CouchDB clients.
CouchDB – Creating a Document Using Curl
To add a document to CouchDB using curl, you must first create a JSON document and save it to a file. For example, we can create a document with two fields, title and content, with the following JSON:
{
“title”: “Example Document”,
“content”: “This is an example document.”
}
Save the file as “example-document.json”, and then use the curl command to POST the document to the database:
curl -X POST http://localhost:5984/my-database -d @example-document.json -H “Content-Type: application/json”
The -X flag specifies the HTTP method to use for the request, in this case POST. The -d flag specifies the data to be sent in the request body, in this case the contents of the example-document.json file. The -H flag specifies the header to be sent in the request, in this case the content type of the body is application/json.
If the request is successful, the output should look like this:
{“ok”:true,”id”:”example-document”,”rev”:”1-5bf8a2a17b2a2f09d2f8e8e17″}
Using a CouchDB Client
If you are using a CouchDB client, you can usually use the client’s UI to add a new document. For example, in Futon, the web-based administration interface for CouchDB, you can click the “New Document” button to create a new document. You can then enter the title and content fields and click the “Save Document” button to add the document to the database.
Creating a Document using cURL Utility
To create a document using cURL, you can use the following command:
curl -X POST -d ‘{“name”: “My Document”}’ http://example.com/documents
Creating a Document using Futon
1. Navigate to the Futon interface by typing in the URL of your CouchDB instance in your web browser.
2. Once the Futon interface is open, click on the “Create Database” button.
3. Enter a name for your database, such as “my_database” and click “Create”.
4. Now the database is created, you can begin creating documents. To do so, click on the name of the database that you just created.
5. Click the “New Document” button to open the document editor.
6. Enter a unique ID for the document, or leave it as the default.
7. Enter your document content in the editor.
8. Click the “Save Document” button to save the document to the database.
9. Your document is now saved and can be accessed by clicking on its ID or name on the left-hand side of the interface.
Add Field to the Document
The new field could be a text field called “Special Instructions” and it would contain any additional information or instructions that a user would need to know in order to complete the document.
Save Document
Futon is a web-based document-oriented database and administration interface. It is part of the Apache CouchDB package. To save a document in Futon, open Futon and select the database to which you want to save the document. Click the “New Document” button, enter the document content in the text box, and click “Save Document”. The document will be stored in the database and you can view it using the Futon interface.
CouchDB – Updating a Document
To update a document in CouchDB, you can use the PUT method. This method requires that you send the data for the new version of the document as part of the request.
You must also include the revision number of the document in the request. This is needed so that CouchDB can detect any concurrent updates that may have occurred since the document was last read.
The PUT request should be sent to the URL of the document. For example, if the document ID is “abc123”, the URL should be “http://example.com/database/abc123”.
The response to a successful PUT request will be a JSON object with the new revision number of the document. This should be stored and used in subsequent requests to update the document.
Updating Documents using cURL
To update a document using cURL, the following command can be used:
curl -X PUT -H “Content-Type: application/json” -d ‘{JSON_DATA}’ http://example.com/api/documents/{document_id}
CouchDB – Deleting a Document
To delete a document in CouchDB, first use an HTTP DELETE request to the API endpoint of the document you wish to delete. You must also provide the revision number of the document you are deleting.
Example:
DELETE /mydatabase/mydoc?rev=1-f3b2a3c3f
Once the request is made, CouchDB will return either a 200 (OK) or a 404 (Not Found) response. If the delete was successful, CouchDB will return a 200 response.
Deleting a Document using cURL Utility
curl -X DELETE http://example.com/documents/document_name.doc
Deleting a Document using Futon
1. Log in to Futon and view the database list.
2. Select the database containing the document you want to delete.
3. Click the All Docs tab to view all of the documents in the database.
4. Click the checkbox next to the document you want to delete.
5. Click the Delete Selected button.
6. Confirm that you want to delete the document by clicking the Delete button.
CouchDB – Attaching Files
CouchDB allows you to attach files to a document. Files can be attached using the CouchDB API. You will need to use the PUT method to attach the file. The API will accept the file as part of the body of the request. You will need to specify the content type and the document the file is being attached to. The API will then return a response with the file’s ID which can be used to reference the file in the document.
Attaching Files using cURL
cURL is a command line tool used to transfer data over a wide range of protocols. It can be used to attach files to a request when making an HTTP POST request. This can be done by including the file location in the request body and setting the content type to the appropriate MIME type. The following example shows how to attach a file named “file.txt” to an HTTP POST request using cURL:
curl -X POST -F “file=@file.txt” -H “Content-Type: text/plain” http://example.com/upload.php
Attaching Files using Futon
Attachments are added to documents in Futon by clicking the “Add Attachment” button in the document view. You will be prompted to select a file from your local computer. Once selected, the file will be uploaded as an attachment to the document. You can also delete existing attachments from the document view by clicking on the “Delete Attachment” button.
Attaching Files using Futon
1. Log into Futon and select the database you want to attach a file to.
2. Click on the “Attachments” tab.
3. Click on the “Attach File” button.
4. Select the file you want to attach and click “Open”.
5. Enter a file name and description, if desired.
6. Click “Upload”.
7. The file will now be attached to the database and can be accessed using the “Attachments” tab.