How to search character by character in mongodb array text field?

问题

I have documents in mongodb are like :

[{
  "_id" : 1,
  "name" : "Himanshu",
  "tags" : ["member", "active"]
},{
  "_id" : 2,
  "name" : "Teotia",
  "tags" : ["employer", "withdrawal"]
},{ 
  "_id" : 3,
  "name" : "John",
  "tags" : ["member", "deactive"]
},{
  "_id" : 4,
  "name" : "Haris",
  "tags" : ["employer", "action"]
}]

1. What I want to search here is if we have array of filter like {"tags" : ["member", "act"]} it will reply back id's 1 and 2 because here member is full match and act partial match in two documents.
2. if I have filter like {"tags" : ["mem"] } then it should reply id's 1 and 3
3. One more case If I have filter like {"tags" : ["member", "active"]} then it should answer only 1.

回答1:

You basically need two concepts here.

1. Convert each input string of the array into an Regular expression anchored to the "start" of the string:

2. Apply the list with the $all operator to ensure "all" matches:

   var filter = { "tags": [ "mem", "active" ] };
   
   // Map with regular expressions
   filter.tags = { "$all": filter.tags.map(t => new RegExpr("^" + t)) };
   // makes filter to { "tags": { "$all": [ /^mem/, /^active/ ] } }
   
   // search for results
   db.collection.find(filter);
   

来源：https://stackoverflow.com/questions/53148402/how-to-search-character-by-character-in-mongodb-array-text-field