- TinyDB Tutorial
- TinyDB - Home
- TinyDB - Introduction
- TinyDB - Environmental Setup
- TinyDB - Insert Data
- TinyDB - Retrieve Data
- TinyDB - Update Data
- TinyDB - Delete Data
- TinyDB - Querying
- TinyDB - Searching
- TinyDB - The where Clause
- TinyDB - The Exists() Query
- TinyDB - The Matches() Query
- TinyDB - The Test() Query
- TinyDB - The Any() Query
- TinyDB - The All() Query
- TinyDB - The one_of() Query
- TinyDB - Logical Negate
- TinyDB - Logical AND
- TinyDB - Logical OR
- TinyDB - Handling Data Query
- TinyDB - Modifying the Data
- TinyDB - Upserting Data
- TinyDB - Retrieving Data
- TinyDB - Document ID
- TinyDB - Tables
- TinyDB - Default Table
- TinyDB - Caching Query
- TinyDB - Storage Types
- TinyDB - Middleware
- TinyDB - Extend TinyDB
- TinyDB - Extensions
- TinyDB Useful Resources
- TinyDB - Quick Guide
- TinyDB - Useful Resources
- TinyDB - Discussion
TinyDB - The where Clause
TinyDB provides the "where" clause that you can use while searching for a particular data. The "where" clause helps by filtering the unwanted data out. With the help of the "where" clause, you can access specific data quickly.
Before using the 'where' clause, we need to first import it. The syntax of "where" clause is given below −
from tinydb import where db.search(where('field') == 'value')
Let's understand the use of 'where' clause with the help of a couple of examples.
The Student Database
For the examples, we will use the following student database.
[ { "roll_number":1, "st_name":"elen", "mark":250, "subject":"TinyDB", "address":"delhi" }, { "roll_number":2, "st_name":"Ram", "mark":[ 250, 280 ], "subject":[ "TinyDB", "MySQL" ], "address":"delhi" }, { "roll_number":3, "st_name":"kevin", "mark":[ 180, 200 ], "subject":[ "oracle", "sql" ], "address":"keral" }, { "roll_number":4, "st_name":"lakan", "mark":200, "subject":"MySQL", "address":"mumbai" }, { "roll_number":5, "st_name":"karan", "mark":275, "subject":"TinyDB", "address":"benglore" } ]
Example 1
Let's use the "where" clause for the subject field −
db.search(where('subject') == 'MySQL')
This query will fetch all the rows where the "subject" field is "MySQL".
[{ 'roll_number': 4, 'st_name': 'lakan', 'mark': 200, 'subject': 'MySQL', 'address': 'mumbai' }]
Example 2
Let's see another use of the "where" clause with the "not equal to" condition −
db.search(where('mark') != 275)
This query will fetch all the rows where the "mark" field is not equal to "275" −
[ { "roll_number":1, "st_name":"elen", "mark":250, "subject":"TinyDB", "address":"delhi" }, { "roll_number":2, "st_name":"Ram", "mark":[ 250, 280 ], "subject":[ "TinyDB", "MySQL" ], "address":"delhi" }, { "roll_number":3, "st_name":"kevin", "mark":[ 180, 200 ], "subject":[ "oracle", "sql" ], "address":"keral" }, { "roll_number":4, "st_name":"lakan", "mark":200, "subject":"MySQL", "address":"mumbai" } ]
To Continue Learning Please Login
Login with Google