In this article, we are going to change DateTime to string in sqlalchemy query in the python programming language.
Database used:
Installation
Syntax to install sqlalchemy and pymysql:
pip install sqlalchmey pymysql
Note: pymysql is a dependency of sqlalchemy which we need to install for this post
First of all, we need to import the module and connect it to the database.
from sqlalchemy import create_engine
user, password, host, database = 'root', '123', 'localhost', 'geeksforgeeks'
engine = create_engine(
url=f'mysql+pymysql://{user}:{password}@{host}/{database}?charset=utf8')
connection = engine.connect()
table_name = 'to_do_list'
Method 1: Using convert function of SQL
So, SQL has a convert function that can be used to change datatype of the column.
The syntax of the function is :
CONVERT(column_name , datatype)
This will convert the column to the given datatype and return the values accordingly.
The SQL query will look like :
SELECT CONVERT(column_name , CHAR) FROM table_name;
We are converting to CHAR as it is one of the data types of string in SQL.
Example:
from sqlalchemy import create_engine
user, password, host, database = 'root', '123', 'localhost', 'geeksforgeeks'
engine = create_engine(
url=f'mysql+pymysql://{user}:{password}@{host}/{database}?charset=utf8')
connection = engine.connect()
table_name = 'to_do_list'
query = f'SELECT CONVERT(start_datetime,char) FROM {table_name}'
result = connection.execute(query)
for elem in result:
value = elem[0]
print(value, type(value))
Output:
Method 2: Using the str function of python :
In this method, we will write a normal "SELECT" query of SQL, execute it, fetch the result and then apply the str function to change the value.
Example:
from sqlalchemy import create_engine
user, password, host, database = 'root', '123', 'localhost', 'geeksforgeeks'
engine = create_engine(
url=f'mysql+pymysql://{user}:{password}@{host}/{database}?charset=utf8')
connection = engine.connect()
table_name = 'to_do_list'
query = f'SELECT start_datetime FROM {table_name}'
result = connection.execute(query)
for elem in result:
value = elem[0]
print(value, type(value))
converted_value = str(value)
print(converted_value, type(converted_value))
# just a line for much more readable output
print("____________________________\n")
Output:
