Develop Reference

MYSQL Search Query when inputs are between range of 0 and 0

I am developing a Flask web application with Python and mysql where one page has a table with data from the MySQL Database. There is a form on the page with search parameters. Some parameters have the option to insert a numerical range (max and minimum). However when I make both the maximum and minimum 0 it returns every single query.
Below is the code from the routing file
if(Value_Min and Value_Max):
if(sql):
sql = sql + ' AND Value BETWEEN %s AND %s'
else:
sql = 'SELECT * FROM database t1 inner join database_table2 t2 on t1.Factor = t2.Factor WHERE t1.Value BETWEEN %s AND %s'
vars.append(Value_Min)
vars.append(Value_Max)
How can I fix this? It seems to work fine for other values so I am not sure what makes 0 any different.
Thank you for your time and help!

"if(Value_Min and Value_Max):" is evaluating to "if(0 and 0)", which is not going to execute the if block. So your SQL "AND Value BETWEEN %s AND %s" is not being added to your sql query at all.
Maybe a better way of doing this is
if (Value_Min is not None) and (Value_Max is not None) :
if(sql):
sql = sql + ' AND Value BETWEEN %s AND %s'
else:
sql = 'SELECT * FROM database t1 inner join database_table2 t2 on t1.Factor = t2.Factor WHERE t1.Value BETWEEN %s AND %s'
vars.append(Value_Min)
vars.append(Value_Max)

pyodbc not updating table

I query a table then loop through it to Update another table.
The console Prints shows correct data.
Not sure how to debug the cursor.execute for the UPDATE query.
It is not updating on the table. It's not a permission issue. If I run update command on my SQL workbench it works fine.
cursor = conn.cursor()
cursor.execute("Select Account_Name FROM dsf_CS_WebAppView")
for row in cursor.fetchall():
try:
cursor.execute("Select fullpath FROM customerdesignmap WHERE
fullpath LIKE '%{}%'".format(row.Account_Name))
rows = cursor.fetchall()
print(len(cursor.fetchall()))
if len(rows) > 0:
for rowb in rows:
print(rowb.fullpath)
print(row.Account_Name)
if len(row.Account_Name) > 2:
cursor.execute("UPDATE customerdesignmap SET householdname = {}, msid = {} WHERE fullpath LIKE '{}'".format(row.Account_Name, row.UniqueProjectNumber, rowb.fullpath))
conn.commit()
except:
pass

Consider a pure SQL solution as SQL Server supports UPDATE and JOIN across multiple tables. This avoids the nested loops, cursor calls, and string formatting of SQL commands.
UPDATE m
SET m.householdname = v.Account_Name,
m.msid = v.UniqueProjectNumber
FROM customerdesignmap m
JOIN dsf_CS_WebAppView v
ON m.fullpath LIKE CONCAT('%', v.Account_Name, '%')
In Python, run above in a single cursor.execute() with commit() call.
cursor.execute('''my SQL Query''')
conn.commit()

Python: Display table names, get user selection, display that table report from SQLite

I have a program that currently reads a database and it will print out the list of tables the current database has.
This is the DB LINK: database (Copy and Paste)
What I am trying to do now is to get user input to display the records from the specific table they chose. I am having trouble to get user selection to display the records. I am using SQLite3 as my main database software.
Also I am very aware of this question on here, but
I keep getting an error when I used the .format(category) embedded on my SQL.
sqlite3.ProgrammingError:
Incorrect number of bindings supplied.
The current statement uses 1, and there are 0 supplied.
This is what I have done so far:
import sqlite3
def get_data():
print("\nSelect a table: ", end="")
category = input()
category = str(category)
if '1' <= category <= '11':
print()
return category
else:
raise ValueError
def get_tables():
database = 'Northwind.db'
connection = sqlite3.connect(database)
c = connection.cursor()
sql = "SELECT * FROM sqlite_master WHERE type='table' AND NAME NOT LIKE 'sqlite_sequence' ORDER BY NAME "
x = c.execute(sql)
for row in x.fetchall():
table = row[1]
print(table)
def main():
category = get_data()
print(category)
get_tables()
if __name__ == "__main__":
main()
I hope this all makes sense. I appreciate the help.
Copy comment: My sql statement look like this:
*)multiple lines for readability
sql = ("SELECT * FROM sqlite_master
WHERE type='table'
AND Name = ?
AND NAME NOT LIKE 'sqlite_sequence'".format(category))

Your SQL string should be:
sql = """SELECT * FROM sqlite_master
WHERE type='table'
AND Name = ?
AND NAME NOT LIKE 'sqlite_sequence'"""
and the execute statement should be:
x = c.execute(sql, (category,))
also ensure that you are passing category as a parameter to your get_tables function.

python cursor.execute returning empty

I have a problem with my python code which I want to use for a REST API server.
The current problem is that my database query is returning null when I know that the value is there
The code for the specific path:
#app.route('/data/active_predicted/<int:ticketId>', methods=['GET'])
def search_db_tickId_act(ticketId):
cursor = db.cursor()
db_query = cursor.execute("select * from active_predicted where ticketId=" + str(ticketId))
json_output = json.dumps(dict(cursor.fetchall()))
cursor.close()
if not cursor.fetchall():
return "Nothing found \n SQL Query: " + "select * from active_predicted where ticketId=" + str(ticketId)
else:
return str(cursor.fetchall())
When I access this URL I get returned the following:
Nothing found SQL Query: select * from active_predicted where ticketId=1324
When I plug this SQL query I get the result I want, 1 row with 2 columns but it seems as though the program cannot locate the row?

The problems:
As #pvg mentioned, you need to escape your input values when querying database;
If you want to fetch a dictionary-like result, passing dictionary=True when you initialize the cursor;
In your original code, you didn't return the variable json_output;
To fetch only one result, use fetchone instead fetchall;
After cursor.close() got called, you can obtain nothing from that cursor no matter you fetched before or not;
Use try-finally to ensure that cursor always get closed (at last).
Here's the fixed code:
#app.route('/data/active_predicted/<int:ticketId>', methods=['GET'])
def search_db_tickId_act(ticketId):
try:
cursor = db.cursor(dictionary=True)
db_query = cursor.execute("select * from active_predicted where ticketId=%s LIMIT 1", ticketId)
row = cursor.fetchone()
if row:
return json.dumps(row)
else:
return "Nothing found \n SQL Query: " + "select * from active_predicted where ticketId=" + str(ticketId)
finally:
cursor.close()

How to test if a table already exists?

I'm working on a scrabblecheat program
Following some examples I have the following code below which uses SQLite for a simple database to store my words.
However it tells me I can't recreate the database table.
How do I write in a check for if there is already a table named spwords, then skip trying to create it?
The error:
(<class 'sqlite3.OperationalError'>, OperationalError('table spwords already exists',), None)
The Code:
def load_db(data_list):
# create database/connection string/table
conn = sqlite.connect("sowpods.db")
#cursor = conn.cursor()
# create a table
tb_create = """CREATE TABLE spwords
(sp_word text, word_len int, word_alpha text, word_score int)
"""
conn.execute(tb_create) # <- error happens here
conn.commit()
# Fill the table
conn.executemany("insert into spwords(sp_word, word_len, word_alpha, word_score) values (?,?,?,?)", data_list)
conn.commit()
# Print the table contents
for row in conn.execute("select sp_word, word_len, word_alpha, word_score from spwords"):
print (row)
if conn:
conn.close()

The query you're looking for is:
SELECT name FROM sqlite_master WHERE type='table' AND name='spwords'
So, the code should read as follows:
tb_exists = "SELECT name FROM sqlite_master WHERE type='table' AND name='spwords'"
if not conn.execute(tb_exists).fetchone():
conn.execute(tb_create)
A convenient alternative for SQLite 3.3+ is to use a more intelligent query for creating tables instead:
CREATE TABLE IF NOT EXISTS spwords (sp_word text, word_len int, word_alpha text, word_score int)
From the documentation:
It is usually an error to attempt to create a new table in a database that already contains a table, index or view of the same name. However, if the "IF NOT EXISTS" clause is specified as part of the CREATE TABLE statement and a table or view of the same name already exists, the CREATE TABLE command simply has no effect (and no error message is returned). An error is still returned if the table cannot be created because of an existing index, even if the "IF NOT EXISTS" clause is specified.

conn = sqlite3.connect('sowpods.db')
curs = conn.cursor()
try:
curs.execute('''CREATE TABLE spwords(sp_word TEXT, word_len INT, word_alpha TEXT,word_score INT)''')
conn.commit()
except OperationalError:
None
https://docs.python.org/2/tutorial/errors.html
I believe if it already exists you can just skip the error and move directly into the inserting of the data

I am not a fan of the bounce the CREATE off the database approach. You should know whether the table exists so that first time initialization can occur.
Here is the same query based answer but based on general purpose functions:
def getTables(conn):
"""
Get a list of all tables
"""
cursor = conn.cursor()
cmd = "SELECT name FROM sqlite_master WHERE type='table'"
cursor.execute(cmd)
names = [row[0] for row in cursor.fetchall()]
return names
def isTable(conn, nameTbl):
"""
Determine if a table exists
"""
return (nameTbl in getTables(conn))
Now the top code is
if not(isTable(conn, 'spwords')):
# create table and other 1st time initialization

Here is an example that shows how to cleanly consume the result from fetchone() call:
table_exists(conn:sqlite3.Connection, tbl_name:string) -> bool:
(count,) = conn.execute("SELECT count(*) FROM sqlite_master WHERE type='table' AND name='{}'".format(tbl_name)).fetchone()
return (count > 0)