TinyDB - Tables

In TinyDB, we can work with multiple tables. These tables have the same properties as the TinyDB class. Let's see how we can create tables in TinyDB and apply various operations on them −

Creating Tables

It’s very easy to create a table in TinyDB. Here's its syntax −

table_object = db.table('table name')

Inserting Values in a Table

To insert data in a specific table, use the following syntax −

table_object.insert({ 'key' : value })

Retreiving Values from a Table

To retrieve values from a table, use the following query −

table_object.all()

Deleting a Table from a Database

To delete a table from a database, use the drop_table() query. Here is its syntax −

db.drop_table('table name')

Delete Multiple Tables from a Database

To delete multiple tables from a database, use the following query −

db.drop_tables()

Let's understand how to use these queries with the help of a few examples. We will use the same student database that we have used in all the previous chapters.

Example 1

Use the following code to create a new table called Student_Detail −

from tinydb import TinyDB, Query
db = TinyDB("student.json")
table_object = db.table('Student_Detail')

Example 2

Next, let's insert values in this new table Student_Detail −

from tinydb import TinyDB, Query
db = TinyDB("student.json")
table_object = db.table('Student_Detail')
table_object.insert({
   'roll_number': 1,
   'st_name': 'elen',
   'mark': 250,
   'subject': 'TinyDB',
   'address': 'delhi'
})

It will return the doc_id of the record inserted in the table.

[1]

To verify, use the following code −

from tinydb import TinyDB, Query
db = TinyDB("student.json")
table_object = db.table('Student_Detail')
table_object.all()

It will show data contained in the Student_Detail table −

{'roll_number': 1, 'st_name': 'elen', 'mark': 250, 'subject': 'TinyDB', 'address': 'delhi'}

Example 3

To see all the tables present in the database, use the following query −

from tinydb import TinyDB, Query
db = TinyDB("student.json")
print(db.tables())

There are two tables inside "student.json". It will show the names of these two tables −

{'Student_Detail', '_default'}

Example 4

Let's see how we can reterive all the values from a table −

from tinydb import TinyDB, Query
db = TinyDB("student.json")
table_object = db.table("Student_Detail")
print(table_object.all())

It will show the following output −

[{
   'roll_number': 1,
   'st_name': 'elen',
   'mark': 250,
   'subject': 'TinyDB',
   'address': 'delhi'
}]

Example 5

Let's see how we can remove a table from a database −

from tinydb import TinyDB, Query
db = TinyDB("student.json")
db.drop_table('Student_Detail')

It will remove the "Student_Detail" table from the database. To remove all the tables from a database, use the "drop_tables()" query −

db.drop_tables()

It will remove all the tables from the database.

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