I can't update database from python - python

I have an sql table which i want to update based on a function
this is my code so far:
def read(conn):
cursor = conn.cursor()
#cursor2 = conn.cursor()
cursor.execute("SELECT All [id],[keyword],[result],[status],[createddate] FROM [Table1].[dbo].[aa]")
index = 1
cursor.execute("set nocount on")
for row in cursor:
s = row[1]
s = re.sub(r'[^\w\s]', '', s)
a=do_func(s)
if a:
cursor.execute("update [Table1].[dbo].[aa] set status = 'completed', result = 'True' where id ={}".format(index))
else:
cursor.execute("update [Table1].[dbo].[aa] set status = 'completed', result = 'False' where id ={}".format(index))
if index == 10:
break
index += 1
i get pyodbc.ProgrammingError: No results. Previous SQL was not a query.
I added "set nocount on" but didn't solve i also tried making a second cursor but also didn't solve problem


okay, see the code: you will need to split the cursor for select and cursor for update, you cannot use both at the same time. And after update, you will need to commit. Let me know if it works.
def read(conn):
selectcursor = conn.cursor()
updatecursor = conn.cursor()
selectcursor.execute("SELECT [id],[keyword],[result],[status],[createddate] FROM [Table1].[dbo].[aa]")
index = 1
result = selectcursor.fetchall()
for row in result:
s = row[1]
s = re.sub(r'[^\w\s]', '', s)
a=do_func(s)
if a:
updatecursor.execute("update [Table1].[dbo].[aa] set status = 'completed', result = 'True' where id ={}".format(index))
updatecursor.commit()
else:
updatecursor.execute("update [Table1].[dbo].[aa] set status = 'completed', result = 'False' where id ={}".format(index))
updatecursor.commit()
if index == 10:
break
index += 1
selectcursor.close()
updatecursor.close()

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for row in rows:
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There is not error being thrown
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You need to commit these changes. Your for loop should look like this:
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There is no way to do what you want, but 3 ways to do very similar:
1.
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cursor.execute(sql)
result = cursor.fetchone()
max_updated_at = result[0]
2.
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dict_cur.execute('select max(updated_at) as max_updated_at ...')
result = dict_cur.fetchone()
max_updated_at = result['max_updated_at']
3.
nt_cur = connection.cursor(cursor_factory=psycopg2.extras.NamedTupleCursor)
nt_cur.execute('select max(updated_at) as max_updated_at ...')
result = nt_cur.fetchone()
max_updated_at = result.max_updated_at

python to write data into table error

write python program to create a mysql table and insert data into this table,the program is as follows:
def pre_data_db_manage(type,data):
conn = pymysql.connect(host="localhost", port=3306, user="root", passwd="********", db="facebook_info",charset="utf8")
cur = conn.cursor()
if type == "pre_davi_group_members_data":
is_exist_table_sql = "SHOW TABLES LIKE 'fb_pre_davi_group_members_posts'"
if cur.execute(is_exist_table_sql) == 0:
create_table_sql = '''CREATE TABLE fb_pre_davi_group_members_posts (id bigint not null primary key auto_increment,userID bigint,userName varchar(128),userURL varchar(256),
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r = re.compile(r'^[a-zA-Z0-9]')
for item in data:
if "'" in item["PostText"]:
item["PostText"] = item["PostText"].replace("'"," ")
if "\\" in item["PostText"]:
item["PostText"] = item["PostText"].replace("\\","\\\\")
for i in item["PostText"]:
result = r.match(i)
if result == None:
print("in re")
item['PostText'] = item['PostText'].replace(i, ' ')
if "nan" in item["SharesCount"]:
item["SharesCount"] = 0
if "nan" in item["LikesCount"]:
item["LikesCount"] = 0
if "nan" in item["CommentsCount"]:
item["CommentsCount"] = 0
if "nan" in item["PostTextLength"]:
item["PostTextLength"] = 0
item["PostTextLength"] = int(item["PostTextLength"])
item["LikesCount"] = int(item["LikesCount"])
item["SharesCount"] = int(item["SharesCount"])
item["CommentsCount"] = int(item["CommentsCount"])
if type == "pre_davi_group_members_data":
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postTime,postText,postTextLength,likesCount,sharesCount,commentsCount,postTextPolarity,postTextSubjectivity) VALUES
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print(insert_sql)
try:
cur.execute(insert_sql)
except Exception as e:
print("insert error")
continue
cur.close()
conn.commit()
conn.close()
and write call statement as follows:
type = "pre_davi_group_members_data"
pre_data_db_manage(type, df_list)
however,when execute this program, found that no data have been inserted into table:fb_pre_davi_group_members_posts,
in the mysql order line, write:
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python loop over sqlite select with .fetchmany() until no entries left

I need to retrieve results from my sqlite3 database 160 rows at a time, and repeat that until there are no rows left for my query, this is what I have:
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c = conn.cursor()
conn.text_factory = str
address = c.execute('select Address from NNDATA where NeuralMagnitude != 0 and NeuralMagnitude is not null and CPID in (select cpids from GRIDCOINTEAM)').fetchmany(160)
conn.text_factory = float
nn_mag = c.execute('select NeuralMagnitude from NNDATA where NeuralMagnitude != 0 and NeuralMagnitude is not null and CPID in (select cpids from GRIDCOINTEAM)').fetchmany(160)
conn.close()
while True:
if nn_mag == ():
sys.exit("Complete")
The reason for sys.exit is I have a bunch of other code to go between conn.close() and while True:, so when the last loop is done I can exit the program. Right now its doing the first pass then the cmd.exe is hanging.
EDIT: Just relaised I dont tell the loop to select the NEXT 160, oh dear!

The fetchmany attribute returns an empty list if there is no item lefts so you can just check the validation of its result. Also note that you should remove the limit from your query and the fetchall. Because the whole essence of using fetchmany is to fetch limited results from your cursor object.
chunk_size = 160
while True:
result = nn_mag.fetchmany(chunk_size)
if not result:
sys.exit("Complete")
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OK the full answer is:
conn = sqlite3.connect("C:\\Users\\%s\\AppData\\Roaming\\GridcoinResearch\\reports\\Rain.db" % user_account)
c = conn.cursor()
position = 00
while True:
conn.text_factory = str
address_db = c.execute('select Address from NNDATA where NeuralMagnitude != 0 and NeuralMagnitude is not null and CPID in (select cpids from GRIDCOINTEAM) limit {}, 160'.format(position)).fetchall()
conn.text_factory = float
rac_db = c.execute('select rac from GRIDCOINTEAM where rac != 0 and rac is not null limit {}, 160'.format(position)).fetchall()
if not address_db:
conn.close()
sys.exit("Complete")
else:
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Here is my code snippet...
First I've called __execute_query function to insert some rows and then to select few rows..
However, if executed a select query the function returns None or Empty rows... However manual sql query returns few rows..
def __execute_query(self, query, parameters = [], set_row_id = False):
conn = MySQL.get_conn()
cursor = conn.cursor()
cursor.execute(query, parameters)
result = None
query_type = query[0:query.find(" ")]
query_type = query_type.lower()
if query_type in ('insert', 'update', 'delete'):
result = cursor.rowcount > 0
if result:
conn.commit()
if query_type == 'insert' and set_row_id == True:
"""
Update the object with the newly saved row ID and mark
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"""
self.__new_row = False
self.__row_id = conn.insert_id()
if self.__row_id == 0 or self.__row_id == "0":
self.__row_id = cursor.lastrowid
else:
result = cursor.fetchall()
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