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docs/querying.md

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+# Querying
+Querying uses a rich expression syntax inspired by the Django ORM, SQLAlchemy,  and Peewee.
+
+The example code defines `Address` and `Customer` models for use with a Redis database with the [RedisJSON](redis-json-url) module installed.
+
+With these two classes defined, you can now:
+
+* Validate data based on the model's type annotations using Pydantic 
+* Persist model instances to Redis as JSON
+* Instantiate model instances from Redis by primary key (a client-generated [ULID](ulid-url))
+* Query on any indexed fields in the models
+
+
+```python
+import datetime
+from typing import Optional
+
+from redis_om.model import (
+    EmbeddedJsonModel,
+    JsonModel,
+    Field,
+)
+
+class Address(EmbeddedJsonModel):
+    address_line_1: str
+    address_line_2: Optional[str]
+    city: str = Field(index=True)
+    state: str = Field(index=True)
+    country: str
+    postal_code: str = Field(index=True)
+
+
+class Customer(JsonModel):
+    first_name: str = Field(index=True)
+    last_name: str = Field(index=True)
+    email: str = Field(index=True)
+    join_date: datetime.date
+    age: int = Field(index=True)
+    bio: Optional[str] = Field(index=True, full_text_search=True,
+                               default="")
+
+    # Creates an embedded model.
+    address: Address
+```
+
+Here are a few example queries that use the models we defined earlier:
+
+```python
+# Find all customers with the last name "Brookins"
+Customer.find(Customer.last_name == "Brookins").all()
+
+# Find all customers that do NOT have the last name "Brookins"
+Customer.find(Customer.last_name != "Brookins").all()
+ 
+# Find all customers whose last name is "Brookins" OR whose age is 
+# 100 AND whose last name is "Smith"
+Customer.find((Customer.last_name == "Brookins") | (
+    Customer.age == 100
+) & (Customer.last_name == "Smith")).all()
+
+# Find all customers who live in San Antonio, TX
+Customer.find(Customer.address.city == "San Antonio",
+              Customer.address.state == "TX")
+```