Suppose I have a three documents where "B" field is present. All the three have 3 different datatypes. How the Index BTREE is stored? And making "B" as an index key is efficient?
Example.
{_id:"1",a:1,b:"abc" } //B is string here
{_id:"1",a:1,b:[1,2,3] } //B is array of numbers
{_id:"1",a:1,b:{x:1,y:"a"} } //B is another nested document