CouchDB document:
"members": [ { "name": "Mark", "age": 35, }, { "name": "Bill", "age": 32, } ] DB Query from PouchDB using PouchDB-Find:
db.createIndex({ index: {fields: [ '_id', 'members.[].name' ]} }).then(() => { db.find({ 'selector': { '_id': { '$gt': null }, 'members': { '$elemMatch': { 'name': {'$eq': 'Bill'} } } }, 'fields': [ 'members' ] }).then((result) => { console.log(result) }).catch((err) => { console.log(err) }) }) The result I get from the above query is the Members array as the whole. But I need to get only the below when I request "name" as "Bill" not the complete array.
{ "name": "Bill", "age": 32, } I did try the fields section in the query but I am unable to find what should be mentioned to get what I want.
1 Answers
Answers 1
It is only possible to specify a set of index independent (static) fields in the doc for find to pick once your selector has chosen a given doc.
Mango queries are a simplified syntax to do common cases and when the structure of your indexes and queries is not typical, you need to use map/reduce directly as indicated in the docs:
The map/reduce API is designed for cases that are too complex for Mango queries
So your changes to the first map/reduce example would look something like:
function mapFun(doc) { if (doc.members) doc.members.forEach( function(m) { emit(m.name, m); // key is name, value is the individual member Object }); }.toString() ... return db.query('index', { key: 'Bill', include_docs: false }); To get output like:
{ "offset" : 0, "rows": [{ "id": "somedoc", "key": "Bill", "value": {name:'Bill', age:32} }], "total_rows" : 1 } 
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