Querying with RedisVL#

In this notebook, we will explore more complex queries that can be performed with redisvl

Before running this notebook, be sure to

  1. Have installed redisvl and have that environment active for this notebook.

  2. Have a running Redis instance with RediSearch > 2.4 running.

import pickle
from jupyterutils import table_print, result_print

# load in the example data and printing utils
data = pickle.load(open("hybrid_example_data.pkl", "rb"))
table_print(data)
useragejobcredit_scoreoffice_locationuser_embedding
john18engineerhigh-122.4194,37.7749b'\xcd\xcc\xcc=\xcd\xcc\xcc=\x00\x00\x00?'
derrick14doctorlow-122.4194,37.7749b'\xcd\xcc\xcc=\xcd\xcc\xcc=\x00\x00\x00?'
nancy94doctorhigh-122.4194,37.7749b'333?\xcd\xcc\xcc=\x00\x00\x00?'
tyler100engineerhigh-122.0839,37.3861b'\xcd\xcc\xcc=\xcd\xcc\xcc>\x00\x00\x00?'
tim12dermatologisthigh-122.0839,37.3861b'\xcd\xcc\xcc>\xcd\xcc\xcc>\x00\x00\x00?'
taimur15CEOlow-122.0839,37.3861b'\x9a\x99\x19?\xcd\xcc\xcc=\x00\x00\x00?'
joe35dentistmedium-122.0839,37.3861b'fff?fff?\xcd\xcc\xcc='
schema = {
    "index": {
        "name": "user_queries",
        "prefix": "user_queries_docs",
        "storage_type": "hash", # default setting -- HASH
    },
    "fields": [
        {"name": "user", "type": "tag"},
        {"name": "credit_score", "type": "tag"},
        {"name": "job", "type": "text"},
        {"name": "age", "type": "numeric"},
        {"name": "office_location", "type": "geo"},
        {
            "name": "user_embedding",
            "type": "vector",
            "attrs": {
                "dims": 3,
                "distance_metric": "cosine",
                "algorithm": "flat",
                "datatype": "float32"
            }

        }
    ],
}
from redisvl.index import SearchIndex

# construct a search index from the schema
index = SearchIndex.from_dict(schema)

# connect to local redis instance
index.connect("redis://localhost:6379")

# create the index (no data yet)
index.create(overwrite=True)
# use the CLI to see the created index
!rvl index listall
16:13:58 [RedisVL] INFO   Indices:
16:13:58 [RedisVL] INFO   1. user_queries
keys = index.load(data)

Hybrid Queries#

Hybrid queries are queries that combine multiple types of filters. For example, you may want to search for a user that is a certain age, has a certain job, and is within a certain distance of a location. This is a hybrid query that combines numeric, tag, and geographic filters.

Tag Filters#

Tag filters are filters that are applied to tag fields. These are fields that are not tokenized and are used to store a single categorical value.

from redisvl.query import VectorQuery
from redisvl.query.filter import Tag

t = Tag("credit_score") == "high"

v = VectorQuery([0.1, 0.1, 0.5],
                "user_embedding",
                return_fields=["user", "credit_score", "age", "job", "office_location"],
                filter_expression=t)


results = index.query(v)
result_print(results)
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
# negation
t = Tag("credit_score") != "high"

v.set_filter(t)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0derricklow14doctor-122.4194,37.7749
0.217882037163taimurlow15CEO-122.0839,37.3861
0.653301358223joemedium35dentist-122.0839,37.3861
# use multiple tags as a list
t = Tag("credit_score") == ["high", "medium"]

v.set_filter(t)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861
# use multiple tags as a set (to enforce uniqueness)
t = Tag("credit_score") == set(["high", "high", "medium"])

v.set_filter(t)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861

What about scenarios where you might want to dynamically generate a list of tags? Have no fear. RedisVL allows you to do this gracefully without having to check for the empty case. The empty case is when you attempt to run a Tag filter on a field with no defined values to match:

Tag("credit_score") == []

An empty filter like the one above will yield a * Redis query filter which implies the base case – there is no filter here to use.

# gracefully fallback to "*" filter if empty case
empty_case = Tag("credit_score") == []

v.set_filter(empty_case)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0derricklow14doctor-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.217882037163taimurlow15CEO-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861

Numeric Filters#

Numeric filters are filters that are applied to numeric fields and can be used to isolate a range of values for a given field.

from redisvl.query.filter import Num

numeric_filter = Num("age") > 15

v.set_filter(numeric_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861
# exact match query
numeric_filter = Num("age") == 14

v.set_filter(numeric_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0derricklow14doctor-122.4194,37.7749
# negation
numeric_filter = Num("age") != 14

v.set_filter(numeric_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.217882037163taimurlow15CEO-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861

Text Filters#

Text filters are filters that are applied to text fields. These filters are applied to the entire text field. For example, if you have a text field that contains the text “The quick brown fox jumps over the lazy dog”, a text filter of “quick” will match this text field.

from redisvl.query.filter import Text

# exact match filter -- document must contain the exact word doctor
text_filter = Text("job") == "doctor"

v.set_filter(text_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0derricklow14doctor-122.4194,37.7749
0.266666650772nancyhigh94doctor-122.4194,37.7749
# negation -- document must not contain the exact word doctor
negate_text_filter = Text("job") != "doctor"

v.set_filter(negate_text_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.217882037163taimurlow15CEO-122.0839,37.3861
0.653301358223joemedium35dentist-122.0839,37.3861
# wildcard match filter
wildcard_filter = Text("job") % "doct*"

v.set_filter(wildcard_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0derricklow14doctor-122.4194,37.7749
0.266666650772nancyhigh94doctor-122.4194,37.7749
# fuzzy match filter
fuzzy_match = Text("job") % "%%engine%%"

v.set_filter(fuzzy_match)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
# conditional -- match documents with job field containing engineer OR doctor
conditional = Text("job") % "engineer|doctor"

v.set_filter(conditional)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0derricklow14doctor-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
# gracefully fallback to "*" filter if empty case
empty_case = Text("job") % ""

v.set_filter(empty_case)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0derricklow14doctor-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.217882037163taimurlow15CEO-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861

Geographic Filters#

Geographic filters are filters that are applied to geographic fields. These filters are used to find results that are within a certain distance of a given point. The distance is specified in kilometers, miles, meters, or feet. A radius can also be specified to find results within a certain radius of a given point.

from redisvl.query.filter import Geo, GeoRadius

# within 10 km of San Francisco office
geo_filter = Geo("office_location") == GeoRadius(-122.4194, 37.7749, 10, "km")

v.set_filter(geo_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0derricklow14doctor-122.4194,37.7749
0.266666650772nancyhigh94doctor-122.4194,37.7749
# within 100 km Radius of San Francisco office
geo_filter = Geo("office_location") == GeoRadius(-122.4194, 37.7749, 100, "km")

v.set_filter(geo_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0derricklow14doctor-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.217882037163taimurlow15CEO-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861
# not within 10 km Radius of San Francisco office
geo_filter = Geo("office_location") != GeoRadius(-122.4194, 37.7749, 10, "km")

v.set_filter(geo_filter)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.217882037163taimurlow15CEO-122.0839,37.3861
0.653301358223joemedium35dentist-122.0839,37.3861

Combining Filters#

In this example, we will combine a numeric filter with a tag filter. We will search for users that are between the ages of 20 and 30 and have a job of “engineer”.

Intersection (“and”)#

t = Tag("credit_score") == "high"
low = Num("age") >= 18
high = Num("age") <= 100

combined = t & low & high

v = VectorQuery([0.1, 0.1, 0.5],
                "user_embedding",
                return_fields=["user", "credit_score", "age", "job",  "office_location"],
                filter_expression=combined)


result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749

Union (“or”)#

The union of two queries is the set of all results that are returned by either of the two queries. The union of two queries is performed using the | operator.

low = Num("age") < 18
high = Num("age") > 93

combined = low | high

v.set_filter(combined)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0derricklow14doctor-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.217882037163taimurlow15CEO-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749

Dynamic Combination#

There are often situations where you may or may not want to use a filter in a given query. As shown above, filters will except the None type and revert to a wildcard filter essentially returning all results.

The same goes for filter combinations which enables rapid reuse of filters in requests with different parameters as shown below. This removes the need for a number of “if-then” conditionals to test for the empty case.

def make_filter(age=None, credit=None, job=None):
    flexible_filter = (
        (Num("age") > age) &
        (Tag("credit_score") == credit) &
        (Text("job") % job)
    )
    return flexible_filter
# all parameters
combined = make_filter(age=18, credit="high", job="engineer")
v.set_filter(combined)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0.109129190445tylerhigh100engineer-122.0839,37.3861
# just age and credit_score
combined = make_filter(age=18, credit="high")
v.set_filter(combined)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
# just age
combined = make_filter(age=18)
v.set_filter(combined)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861
# no filters
combined = make_filter()
v.set_filter(combined)
result_print(index.query(v))
vector_distanceusercredit_scoreagejoboffice_location
0johnhigh18engineer-122.4194,37.7749
0derricklow14doctor-122.4194,37.7749
0.109129190445tylerhigh100engineer-122.0839,37.3861
0.158808946609timhigh12dermatologist-122.0839,37.3861
0.217882037163taimurlow15CEO-122.0839,37.3861
0.266666650772nancyhigh94doctor-122.4194,37.7749
0.653301358223joemedium35dentist-122.0839,37.3861

Filter Queries#

In some cases, you may not want to run a vector query, but just use a FilterExpression similar to a SQL query. The FilterQuery class enable this functionality. It is similar to the VectorQuery class but soley takes a FilterExpression.

from redisvl.query import FilterQuery

has_low_credit = Tag("credit_score") == "low"

filter_query = FilterQuery(
    return_fields=["user", "credit_score", "age", "job", "location"],
    filter_expression=has_low_credit
)

results = index.query(filter_query)

result_print(results)
usercredit_scoreagejob
derricklow14doctor
taimurlow15CEO

Count Queries#

In some cases, you may need to use a FilterExpression to execute a CountQuery that simply returns the count of the number of entities in the pertaining set. It is similar to the FilterQuery class but does not return the values of the underlying data.

from redisvl.query import CountQuery

has_low_credit = Tag("credit_score") == "low"

filter_query = CountQuery(filter_expression=has_low_credit)

count = index.query(filter_query)

print(f"{count} records match the filter expression {str(has_low_credit)} for the given index.")
2 records match the filter expression @credit_score:{low} for the given index.

Range Queries#

Range Queries are a useful method to perform a vector search where only results within a vector distance_threshold are returned. This enables the user to find all records within their dataset that are similar to a query vector where “similar” is defined by a quantitative value.

from redisvl.query import RangeQuery

range_query = RangeQuery(
    vector=[0.1, 0.1, 0.5],
    vector_field_name="user_embedding",
    return_fields=["user", "credit_score", "age", "job", "location"],
    distance_threshold=0.2
)

# same as the vector query or filter query
results = index.query(range_query)

result_print(results)
vector_distanceusercredit_scoreagejob
0johnhigh18engineer
0derricklow14doctor
0.109129190445tylerhigh100engineer
0.158808946609timhigh12dermatologist

We can also change the distance threshold of the query object between uses if we like. Here we will set distance_threshold==0.1. This means that the query object will return all matches that are within 0.1 of the query object. This is a small distance, so we expect to get fewer matches than before.

range_query.set_distance_threshold(0.1)

result_print(index.query(range_query))
vector_distanceusercredit_scoreagejob
0johnhigh18engineer
0derricklow14doctor

Range queries can also be used with filters like any other query type. The following limits the results to only include records with a job of engineer while also being within the vector range (aka distance).

is_engineer = Text("job") == "engineer"

range_query.set_filter(is_engineer)

result_print(index.query(range_query))
vector_distanceusercredit_scoreagejob
0johnhigh18engineer

Other Redis Queries#

Sometimes there may be a case where RedisVL does not cover the explicit functionality required by the query either because of new releases that haven’t been implemented in the client, or because of a very specific use case. In these cases, it is possible to use the SearchIndex.search method to execute query with a redis-py Query object or through a raw redis string.

For example

Redis-Py#

# Manipulate the Redis-py Query object
redis_py_query = v.query

# choose to sort by age instead of vector distance
redis_py_query.sort_by("age", asc=False)

# run the query with the ``SearchIndex.search`` method
result = index.search(redis_py_query, v.params)
result_print(result)
vector_distanceageusercredit_scorejoboffice_location
0.109129190445100tylerhighengineer-122.0839,37.3861
0.26666665077294nancyhighdoctor-122.4194,37.7749
0.65330135822335joemediumdentist-122.0839,37.3861
018johnhighengineer-122.4194,37.7749
0.21788203716315taimurlowCEO-122.0839,37.3861
014derricklowdoctor-122.4194,37.7749
0.15880894660912timhighdermatologist-122.0839,37.3861

Raw Redis Query String#

So one case might be where you simply want to have a search that only filters on a tag field and don’t need other functionality. Conversely, you may need to have a query that is more complex than what is currently supported by RedisVL. In these cases, you can use the SearchIndex.search again with just a raw redis query string.

t = Tag("credit_score") == "high"

str(t)
'@credit_score:{high}'
results = index.search(str(t))
for r in results.docs:
    print(r.__dict__)
{'id': 'user_queries_docs:6ae49de28548476ea4896f6cdb35f617', 'payload': None, 'user': 'john', 'age': '18', 'job': 'engineer', 'credit_score': 'high', 'office_location': '-122.4194,37.7749', 'user_embedding': '==\x00\x00\x00?'}
{'id': 'user_queries_docs:14af692b215a402580991c1ea464df9d', 'payload': None, 'user': 'nancy', 'age': '94', 'job': 'doctor', 'credit_score': 'high', 'office_location': '-122.4194,37.7749', 'user_embedding': '333?=\x00\x00\x00?'}
{'id': 'user_queries_docs:435f00b6002c4ce4b08303bebacfda76', 'payload': None, 'user': 'tyler', 'age': '100', 'job': 'engineer', 'credit_score': 'high', 'office_location': '-122.0839,37.3861', 'user_embedding': '=>\x00\x00\x00?'}
{'id': 'user_queries_docs:22bcd56418c744009052c3391c9b6a78', 'payload': None, 'user': 'tim', 'age': '12', 'job': 'dermatologist', 'credit_score': 'high', 'office_location': '-122.0839,37.3861', 'user_embedding': '>>\x00\x00\x00?'}

Inspecting Queries#

In this example, we will show how to inspect the query that is generated by RedisVL. This can be useful for debugging purposes or for understanding how the query is being executed.

Let’s again take the example of a query that combines a numeric filter with a tag filter. This will search for users that are between the ages of between 18 and 100, have a high credit score, and sort by closest vector distance to the query vector.

t = Tag("credit_score") == "high"
low = Num("age") >= 18
high = Num("age") <= 100

combined = t & low & high

v.set_filter(combined)

# Using the str() method, you can see what Redis Query this will emit.
str(v)
'((@credit_score:{high} @age:[18 +inf]) @age:[-inf 100])=>[KNN 10 @user_embedding $vector AS vector_distance] RETURN 6 user credit_score age job office_location vector_distance SORTBY vector_distance ASC DIALECT 2 LIMIT 0 10'
# Cleanup
index.delete()