Efficient text searching across multiple string fields in mongo using nodejs - node.js

Question

There are like 10000 records like this that are stored in mongo. How to search the following efficiently in node.js. The search criteria can be based on any of the following 3 fields in mongo. The search criteria will come from front end and they can search userID or employeeName or department. For search only one input is going to be taken i.e only one field which can match any of these fields something like google search.
{
"userID": "01000900",
"employeeName": "A Abc",
"department": "Replenishment Boston"
},
{
"userID": "01001024",
"employeeName": "K Gbc",
"department": "Sales S-II - MA Core Urb"
},
{
"userID": "01001023",
"employeeName": "Ga Va",
"department": "Sales Phoenix"
},
{
"userID": "01000282",
"employeeName": "D Din",
"department": "Sales S-II - California - Me"
}

Answer 1

Assume searchText is the value which you are getting from client. Use regular expression.
{
$or:[
{userId:{$regex: searchText, $options: 'i'}},
{employeeName:{$regex: searchText, $options: 'i'}},
{department:{$regex: searchText, $options: 'i'}}
]
}

Answer 2

You can use Text index on all 3 fields like following:
db.collection.createIndex(
{
userID: "text",
employeeName: "text",
department: "text"
}
)
The query db.collection.find( { $text: { $search: "string from input" } } )
should do something like google search. Docs for text query syntax.

Answer 3

You can create index for each field. In this way the when you fins some data it will not scan the whole document. The search will be based on the index. So you will get the result instantaneously. Now for creating index. Suppose you want to create an index on employeeName then do the following:
db.collectionName.createIndex({employeeName:1});