Good, what happens is that I have two tables in the same database, the first table I will call patient, the second appointment .... both have the same column that is "cc" .... I look for a date, That match my table in quotes and grab the "cc", then go to the patient table and bring the name in such a way that I print name + cc + date ...... what worries me is how I make that link Between the tables with python, attached images to see the database and part of the code of which I try to join and print the matches of "cc".
Thank you for your cooperation.
Data from the first table
Data from the second table
You didn't mention what library you are/intend to use for MySQL. I will assume pymssql. Here is a simple example to get you started based off their documentation and Hatik's query.
import pymssql
conn = pymssql.connect("localhost", "admin", "password", "database")
cursor = conn.cursor()
cursor.execute("""
SELECT B.NAME, B.CC, C.DATE FROM
APPOINTMENT A LEFT JOIN PATIENT B ON A.CC = B.CC
""")
row = cursor.fetchone()
while row:
print row
row = cursor.fetchone()
conn.close()
Related
I am trying to use a registered virtual table as a table in a SQL statement using a connection to another database. I can't just turn the column into a string and use that, I need the table/dataframe itself to work in the statement and join with the other tables in the SQL statment. I'm trying this out on an Access database to start. This is what I have so far:
import pyodbc
import pandas as pd
import duckdb
conn = duckdb.connect()
starterset = pd.read_excel (r'e:\Data Analytics\Python_Projects\Applications\DB_Test.xlsx')
conn.register("test_starter", starterset)
IDS = conn.execute("SELECT * FROM test_starter WHERE ProjectID > 1").fetchdf()
StartDate = '1/1/2015'
EndDate = '12/1/2021'
# establish the connection
connt = pyodbc.connect(r'Driver={Microsoft Access Driver (*.mdb, *.accdb)};DBQ=E:\Databases\Offline.accdb;')
cursor = conn.cursor()
# Run the query
query = ("Select ProjectID, Revenue, ClosedDate from Projects INNER JOIN " + IDS + " Z on Z.ProjectID = Projects.ProjectID "
"where ClosedDate between #" + StartDate + "# and #" + EndDate + "# AND Revenue > 0 order by ClosedDate")
sfd
df = pd.read_sql(query, connt)
df.to_excel(r'TEMP.xlsx', index=False)
os.system("start EXCEL.EXE TEMP.xlsx")
# Close the connection
cursor.close()
connt.close()
I have a list of IDs in the excel sheet that I'm trying to use as a filter from the database query. Ultimately, this will form into several criteria from the same table: dates, revenue, and IDs among others.
Honestly, I'm surprised I'm having so much trouble doing this. In SAS, with PROC SQL, it's so easy, but I can't get a dataframe to interface within the SQL parameters how I need it to. Am I making a syntax mistake?
Most common error so far is "UFuncTypeError: ufunc 'add' did not contain a loop with signature matching types (dtype('<U55'), dtype('<U55')) -> dtype('<U55')", but the types are the same.
It looks like you are pushing the contents of a DataFrame into an Access database query. I don't think there is a native way to do this in Pandas. The technique I use is database vendor specific, but I just build up a text string as either a CTE/WITH Clause or a temporary table.
Ex:
"""WITH my_data as (
SELECT 'raw_text_within_df' as df_column1, 'raw_text_within_df' as df_column2
UNION ALL
SELECT 'raw_text_within_df' as df_column1, 'raw_text_within_df' as df_column2
UNION ALL
...
)
[Your original query here]
"""
I have a GUI interacting with my database, and MySQL database has around 50 tables. I need to search each table for a value and return the field and key of the item in each table if it is found. I would like to search for partial matches. ex.( Search Value = "test", "Protest", "Test123" would be matches. Here is my attempt.
def searchdatabase(self, event):
print('Searching...')
self.connect_mysql() #Function to connect to database
d_tables = []
results_list = [] # I will store results here
s_string = "test" #Value I am searching
self.cursor.execute("USE db") # select the database
self.cursor.execute("SHOW TABLES")
for (table_name,) in self.cursor:
d_tables.append(table_name)
#Loop through tables list, get column name, and check if value is in the column
for table in d_tables:
#Get the columns
self.cursor.execute(f"SELECT * FROM `{table}` WHERE 1=0")
field_names = [i[0] for i in self.cursor.description]
#Find Value
for f_name in field_names:
print("RESULTS:", self.cursor.execute(f"SELECT * FROM `{table}` WHERE {f_name} LIKE {s_string}"))
print(table)
I get an error on print("RESULTS:", self.cursor.execute(f"SELECT * FROM `{table}` WHERE {f_name} LIKE {s_string}"))
Exception: (1054, "Unknown column 'test' in 'where clause'")
I use a similar insert query that works fine so I am not understanding what the issue is.
ex. insert_query = (f"INSERT INTO `{source_tbl}` ({query_columns}) VALUES ({query_placeholders})")
May be because of single quote you have missed while checking for some columns.
TRY :
print("RESULTS:", self.cursor.execute(f"SELECT * FROM `{table}` WHERE '{f_name}' LIKE '{s_string}'"))
Have a look -> here
Don’t insert user-provided data into SQL queries like this. It is begging for SQL injection attacks. Your database library will have a way of sending parameters to queries. Use that.
The whole design is fishy. Normally, there should be no need to look for a string across several columns of 50 different tables. Admittedly, sometimes you end up in these situations because of reasons outside your control.
I'm trying to accomplish a very simple task:
Create a table in SQLite
Insert several rows
Query a single column in the table and pull back each row
Code to create tab:
import sqlite3
sqlite_file = '/Users/User/Desktop/DB.sqlite'
conn = sqlite3.connect(sqlite_file)
c = conn.cursor()
c.execute('''CREATE TABLE ListIDTable(ID numeric, Day numeric, Month
numeric, MonthTxt text, Year numeric, ListID text, Quantity text)''')
values_to_insert = [
(1,16,7,"Jul",2015,"XXXXXXX1","Q2"),
(2,16,7,"Jul",2015,"XXXXXXX2","Q2"),
(3,14,7,"Jul",2015,"XXXXXXX3","Q1"),
(4,14,7,"Jul",2015,"XXXXXXX4","Q1")] #Entries continue similarly
c.executemany("INSERT INTO ListIdTable (ID, Day, Month, MonthTxt,
Year, ListID, Quantity) values (?,?,?,?,?,?,?)", values_to_insert)
conn.commit()
conn.close()
When I look at this table in SQLite DB Browser, everything looks fine.
Here's my code to try and query the above table:
import sqlite3
sqlite_file = '/Users/User/Desktop/DB.sqlite'
conn = sqlite3.connect(sqlite_file)
conn.row_factory = sqlite3.Row
c = conn.cursor()
for row in c.execute('select * from ListIDTable'):
r = c.fetchone()
ID = r['ID']
print (ID)
I should get a print out of 1, 2, 3, 4.
However, I only get 2 and 4.
My code actually uploads 100 entries to the table, but still, when I query, I only get ID printouts of even numbers (i.e. 2, 4, 6, 8 etc.).
Thanks for any advice on fixing this.
You don't need to fetchone in the loop -- The loop is already fetching the values (one at a time). If you fetchone while you're iterating, you'll only see half the data because the loop fetches one and then you immediately fetch the next one (without ever looking at the one that was fetched by the loop):
for r in c.execute('select * from ListIDTable'):
ID = r['ID']
print (ID)
I have the data in pandas dataframe which I am storing in SQLITE database using Python. When I am trying to query the tables inside it, I am able to get the results but without the column names. Can someone please guide me.
sql_query = """Select date(report_date), insertion_order_id, sum(impressions), sum(clicks), (sum(clicks)+0.0)/sum(impressions)*100 as CTR
from RawDailySummaries
Group By report_date, insertion_order_id
Having report_date like '2014-08-12%' """
cursor.execute(sql_query)
query1 = cursor.fetchall()
for i in query1:
print i
Below is the output that I get
(u'2014-08-12', 10187, 2024, 8, 0.3952569169960474)
(u'2014-08-12', 12419, 15054, 176, 1.1691244851866613)
What do I need to do to display the results in a tabular form with column names
In DB-API 2.0 compliant clients, cursor.description is a sequence of 7-item sequences of the form (<name>, <type_code>, <display_size>, <internal_size>, <precision>, <scale>, <null_ok>), one for each column, as described here. Note description will be None if the result of the execute statement is empty.
If you want to create a list of the column names, you can use list comprehension like this: column_names = [i[0] for i in cursor.description] then do with them whatever you'd like.
Alternatively, you can set the row_factory parameter of the connection object to something that provides column names with the results. An example of a dictionary-based row factory for SQLite is found here, and you can see a discussion of the sqlite3.Row type below that.
Step 1: Select your engine like pyodbc, SQLAlchemy etc.
Step 2: Establish connection
cursor = connection.cursor()
Step 3: Execute SQL statement
cursor.execute("Select * from db.table where condition=1")
Step 4: Extract Header from connection variable description
headers = [i[0] for i in cursor.description]
print(headers)
Try Pandas .read_sql(), I can't check it right now but it should be something like:
pd.read_sql( Q , connection)
Here is a sample code using cx_Oracle, that should do what is expected:
import cx_Oracle
def test_oracle():
connection = cx_Oracle.connect('user', 'password', 'tns')
try:
cursor = connection.cursor()
cursor.execute('SELECT day_no,area_code ,start_date from dic.b_td_m_area where rownum<10')
#only print head
title = [i[0] for i in cursor.description]
print(title)
# column info
for x in cursor.description:
print(x)
finally:
cursor.close()
if __name__ == "__main__":
test_oracle();
I have a small database which is legacy from an almost defunct project. This database has a "Patients" table with individual personal data and an unique "Id" field, and an "Exams" table with some fields for each exam, one of these fields being "Patient_Id".
What I want is, for a given patient (row from "Pacientes" table) the exams (rows) from "Exames" table whose "Patient_Id" matches that of the given patient.
I am very beginner with SQL, so if the question is very naive, I apologize.
My working code is the following, but I am using a for loop while I would much rather have a SQL query (which is the very point of using databases, I think...):
#!/usr/bin/env python
# coding: utf-8
import os, sqlite3
conn = sqlite3.connect('BDdata.db3')
conn.row_factory = sqlite3.Row
c = conn.cursor()
c.execute('SELECT * FROM Exames')
exams = c.fetchall()
c.execute('SELECT * FROM Pacientes')
for row in c:
Nome = row['nome']
ID = row['Id']
for exam in exams: # I would like to replace this loop
if exam['Id_Paciente'] == ID: # with a SQL query meaning
print exam['File']
============================
An answer to a similar question seems to be what I want, but I have no idea how to do this in Python with sqlite3 module, much less what in this expression is essential and what is incidental, or what is the syntax structure:
Selecting rows from a table by One a field from other table
SELECT i.prof_image
FROM profile_images i
WHERE cat_id = (select max(cat_id) from images_cat)
I think the following should do what you want:
...
c = conn.cursor()
c.execute('SELECT * FROM Pacientes')
for row in c.fetchall():
Nome = row['nome']
ID = row['Id']
c.execute('SELECT File FROM Exames WHERE Id_Paciente=?', [ID])
for exam in c:
print exam['File']