I am trying to search for a document in elasticsearch.
Field name is sum and Field value is 'SUM-123'
I created a bool query to matchQuery('sum','SUM-123').
But it is not returning the exact sum field documents instead it is returning the documents with different field values.
Thanks.
If you want to do an exact string matching, you should not analyzed your index.
More info here
Related
I am trying to do an aggregate join to find patient information in the 'patients' table based on 'patient_id' field in the bookings table. Aggregate join is not returning results even though there are matching records in the 'patients' table. Am I doing something wrong?
If the _id field in the "patients" collection is an ObjectId, it won't match when you compare to the string value stored in patient_id. You can use the $addFields aggregation step to add a new field to the documents with the "patient_id" field cast to an ObjectId, but I'd advise you to instead store reference id's as ObjectIds
I am very beiginer in Solr and I am trying to do query on my data. I am trying to find data with name=plant and sort it by maximum price
my schema for both name and price is text type.
for eg let say data is
name:abc, price:25;
name:plant, price:35;
name:plant,price:45; //1000 other data
My Approach
/query?q=(name:"Plant")&stopwords=true
but above is giving me result of plants but I am not sure how to sort result using price feild
Any help will be appreciated
You can use the sort param for achieving the sorting.
Your query would be like q=(name:"Plant")&sort=price desc
The sort parameter arranges search results in either ascending (asc)
or descending (desc) order. The parameter can be used with either
numerical or alphabetical content. The directions can be entered in
either all lowercase or all uppercase letters (i.e., both asc or ASC).
Solr can sort query responses according to document scores or the
value of any field with a single value that is either indexed or uses
DocValues (that is, any field whose attributes in the Schema include
multiValued="false" and either docValues="true" or indexed="true" – if
the field does not have DocValues enabled, the indexed terms are used
to build them on the fly at runtime), provided that:
the field is non-tokenized (that is, the field has no analyzer and its
contents have been parsed into tokens, which would make the sorting
inconsistent), or
the field uses an analyzer (such as the KeywordTokenizer) that
produces only a single term.
I have inserted some json data into mongodb and I wanted to perform a simple search by matching only the values irrespective of the keys (Since keys are different for different documents) and wanted to return the id of the document. I don't know how to compare only by values in mongodb.
Example: Suppose if am searching for word "Knowledge" it should return all the ids of the document which contain the word "Knowledge" irrespective of its key value.
You need to use Wildcard Text Indexes.
db.collection.createIndex( { "$**": "text" } )
If there is a static superset of fieldnames, you may find text indexes and the $text query operator useful for word-based searches.
Create the text index on every potential field, and those contained in each document will be included.
From the MongoDB documentation they have stated six index types :
Single Field Index
Compound Index
Multikey index
Geospacial index
Text index
Hashed index
The documentation has also stated four index properties.
Unique Indexes
Partial indexes
Sparse Indexes
TTL Indexes
My questions are:
Can any index type have any index property?
Can an index type have more than one index property?
According to the docs: MongoDB creates a unique index on the _id field during the creation of
a collection. Does this mean when I search by Id MongoDB does not do a collection scan but instead uses the id index to execute the query efficiently? Or is the default id index just for uniqueness only? Does a unique index property always support faster queries?
I am using MongoDB via mongoose. When defining a schema in node.js does the field unique: true imply indexing of that will result to efficient search as opposed to a collection scan?
Can materialized views be indexed in MongoDB? If so how?
In the MongoDB documentation it states that MongoDB provides a number of different index types to support specific types of data and queries. Gut there is no explanation of what index properties are. How would you define index properties?
Can any index type have any index property?
Can an index type have more than one index property?
You can test yourself and find out.
Does this mean when I search by Id MongoDB does not do a collection scan but instead uses the id index to execute the query efficiently?
Yes.
Does a unique index property always support faster queries?
Uniqueness refers to a restriction on data which can be placed in the field which is indexed. Both unique and non-unique indexes allow fast retrieval of data queried by indexed fields.
Can materialized views be indexed in MongoDB?
If you are talking about https://docs.mongodb.com/manual/core/materialized-views/, "materialized views" in MongoDB are orthogonal to indexes. You can add indexes on what this page refers to as "output collection" (the argument to $merge) if you wish to query the "materialized view" efficiently.
MongoDB provides a number of different index types to support specific types of data and queries.
Geospatial index supports geo queries. Text index supports text search. Other indexes are general-purpose.
Lucene.Net -
Is there a way to query for documents that contain a particular field.
Lets say some of my documents have a field 'foo' and some do not.
I want to find all documents that have the field 'foo' - regardless of what the value of foo is.
How do I do this? Is it some sort of TermQuery?
Try foo:[* TO *]
should work for all non-null values of field 'foo'