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jq - A command-line JSON processor. You can use it to parse, filter and manipulate CouchDB's JSON output.
jgrep - A Ruby-based CLI tool and API for parsing and displaying JSON data using a logical expression syntax.
mock couch - A node.js module to mock a CouchDB server for unit testing CouchDB based apps.
couch-cli - Command line interface to facilitate CouchDB replication and other administrative tasks (Groovy).
couchdb-utils - A fast and portable CouchDB command line utility (Go).
covercouch - Per-document r/w/d ACL for CouchDB, preserves original CouchDB API untouched.
- lava - a minimal command-line shell script to keep your views toasty warm and up-to-date with their corresponding DBs (shell + jq and curl)
Commercial
CouchDB Pumper - a tool to migrate Oracle data to CouchDB and back.
NoSQLViewer - a free tool which provides convenient GUI data management framework for CouchDB
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