how to save or create a persist dataframe that its not changed on each selection or click of a button Because on each click the code is rerun from the beginning from top to down.
what i want is to save the created dataframe using st.session_state but i don’t know how to use it yet.
what I want is to do something similar to the incremental number below But instead i want to make it to the df_result_search
code:
import pandas as pd
import streamlit as st
df_result_search = pd.DataFrame.from_records(rows, columns = [column[0] for column in cursor.description])
if 'count' not in st.session_state:
st.session_state.count = 0
st.write("you are out of the session")
else:
st.write("you are in the session")
st.dataframe(df_result_search)
df_len = range(len(df_result_search.index))
s = st.selectbox('Select index',options=df_len)
st.write(s)
expander_updates_fields = st.beta_expander('Update Records')
with expander_updates_fields:
for i, col in enumerate(df.columns):
val_update = st_input_update('Update {} from {} to:'.format(col, df[col].values[s]))
expander_updates_fields.markdown(val_update, unsafe_allow_html=True)
if st.button("Increment"):
st.session_state.count += 1
st.write('Count = ', st.session_state.count)
so how this can be done ??
Hey @leb_dev ,
You can do the following to work with SessionState:
- Copy this SessionState code (SessionState.py) into a .py file and name it SessionState.py in your project folder
- import SessionState and initialiaze count in sessionstate like the following:
import SessionState
ss = SessionState.get(count=0)
- Afterwards, to keep the value of count make sure you increment it from sessionstate variable ss.
Let’s us know if this helped you out !
I tried your answer and this what i wrote:
ss = SessionState.get(count=0)
if st.button("Increment"):
ss += 1
st.write('Count = ', ss)
it display the below error:
TypeError: unsupported operand type(s) for +=: 'SessionState' and 'int'
Traceback:
File "F:\AIenv\lib\site-packages\streamlit\script_runner.py", line 349, in _run_script
exec(code, module.__dict__)File "f:\AIenv\streamlit\app2.py", line 1097, in <module>
main()File "f:\AIenv\streamlit\app2.py", line 522, in main
ss += 1
Hey @leb_dev ,
In order for the incrementation to work you have to increment ss.count instead of ss, like the following:
import streamlit as st
import SessionState
ss = SessionState.get(count=0)
if st.button("Increment"):
ss.count += 1
st.write('Count = ', ss.count)
By implementing the code above, it should be working.
Let us know if this helped you out !
so how about save or preserve the dataframe after the change in selectbox as i asked in my question
In order to keep your dataframe persistent, you can add a second variable inside sessionstate and give your dataframe as a value. Let’s add this to our previous program:
import streamlit as st
import numpy as np
import SessionState
dataframe = np.random.randn(10, 20)
ss = SessionState.get(count=0, df=dataframe)
st.dataframe(ss.df)
if st.button("Increment"):
ss.count += 1
st.write('Count = ', ss.count)
We have created a random dataframe and we persisted it in a way that it won’t change when our page refreshes.
Let us know if this helped
i tried your answer but it display the below error:
AttributeError: 'SessionState' object has no attribute 'df'
Traceback:
File "F:\AIenv\lib\site-packages\streamlit\script_runner.py", line 349, in _run_script
exec(code, module.__dict__)File "f:\AIenv\streamlit\app2.py", line 1142, in <module>
st.dataframe(ss.df)
I had the same error at first, but it was solved by reloading the page and/or changing the name of the dataframe inside sessionstate.
Keep us updated!
Hi @leb_dev,
Here’s an example I put together demonstrating how to delete columns from a dataframe based on user input, and store the resulting dataframe as Session State variable.
import pandas as pd
import streamlit as st
@st.cache
def load_data():
df = pd.read_csv("https://github.com/selva86/datasets/raw/master/Auto.csv")
return df
# callback to remove column from dataframe and store result in session state
def persist_dataframe():
# drop column from dataframe
delete_col = st.session_state["delete_col"]
if delete_col in st.session_state["updated_df"]:
st.session_state["updated_df"] = st.session_state["updated_df"].drop(
columns=[delete_col]
)
else:
st.sidebar.warning("Column previously deleted. Select another column.")
with col2:
st.write("Updated dataframe")
st.dataframe(st.session_state["updated_df"])
st.write(st.session_state["updated_df"].columns.tolist())
df = load_data()
# initialize session state variable
if "updated_df" not in st.session_state:
st.session_state.updated_df = df
# display original df in col1 and updated df in col2
col1, col2 = st.beta_columns(2)
with col1:
st.write("Original dataframe")
st.dataframe(df)
st.write(df.columns.tolist())
with st.sidebar.form("my_form"):
index = df.columns.tolist().index(
st.session_state["updated_df"].columns.tolist()[0]
)
st.selectbox(
"Select column to delete", options=df.columns, index=index, key="delete_col"
)
delete = st.form_submit_button(label="Delete", on_click=persist_dataframe)
Output:
Best, 
Snehan
about the error above you were right i need to refresh the page.
But when i tried you answer into my code it still not working and the dataframe is not persist.
code:
import streamlit as st
import pandas as pd
df = pd.read_sql_query('select * from testDB.dbo.t1',con)
with st.form(key='Search_form'):
all_columns = df.columns.tolist()
st_input_update = st.number_input if is_numeric_dtype(all_columns) else st.text_input
search_term=st_input_update("Enter Search Term")
if st.form_submit_button("search"):
if len(search_term)>0:
sql='select * from testDB.dbo.t1 where last LIKE ? or first LIKE ? '
param0=f'%{search_term}%'
param1=f'%{search_term}%'
rows = cursor.execute(sql, param0,param1).fetchall()
df_result_search = pd.DataFrame.from_records(rows, columns = [column[0] for column in cursor.description])
ss = SessionState.get(df=df_result_search)
st.dataframe(ss.df)
df_len = range(len(df_result_search.index))
s = st.selectbox('Select index',options=df_len)
st.write(s)
expander_updates_fields = st.beta_expander('Update Records')
with expander_updates_fields:
for i, col in enumerate(df.columns):
val_update = st_input_update('Update {} from {} to:'.format(col, df[col].values[s]))
expander_updates_fields.markdown(val_update, unsafe_allow_html=True)
1 Like
So if i want to apply your code into mine is this how it can be wrote ?
code:
import streamlit as st
import pandas as pd
df = pd.read_sql_query('select * from testDB.dbo.t1',con)
with st.form(key='Search_form'):
all_columns = df.columns.tolist()
st_input_update = st.number_input if is_numeric_dtype(all_columns) else st.text_input
search_term=st_input_update("Enter Search Term")
if st.form_submit_button("search"):
if len(search_term)>0:
sql='select * from testDB.dbo.t1 where last LIKE ? or first LIKE ? '
param0=f'%{search_term}%'
param1=f'%{search_term}%'
rows = cursor.execute(sql, param0,param1).fetchall()
df_result_search = pd.DataFrame.from_records(rows, columns = [column[0] for column in cursor.description])
st.session_state["df_result_search"]
if 'df_result_search' not in st.session_state:
st.session_state.df_result_search = df_result_search
st.write("you are out of the session")
else:
st.write("you are in the session")
st.session_state.df_result_search = df_result_search
st.dataframe(st.session_state["df_result_search"])
df_len = range(len(df_result_search.index))
s = st.selectbox('Select index',options=df_len)
st.write(s)
expander_updates_fields = st.beta_expander('Update Records')
with expander_updates_fields:
for i, col in enumerate(df.columns):
val_update = st_input_update('Update {} from {} to:'.format(col, df[col].values[s]))
expander_updates_fields.markdown(val_update, unsafe_allow_html=True)