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Is there any cleaner way to check if tuple or row are meet a condition in a database using mysql connector?

I am using mysql.connector in Python to manage particular database, I am trying to check in a table if there is any tuple or row that meet a condition, here is the code:
db_campaign = mysql.connector.connect(
host="localhost",
user="root",
passwd="pass",
database="campaign"
)
cursor = db_campaign.cursor()
query = "SELECT EXISTS(SELECT * FROM transaction WHERE id = 10)"
cursor.execute(query)
for val in cursor:
if val[0] == 1:
found = True
Is there any way to make this cleaner?

cursor = db_campaign.cursor()
query = "SELECT 1 FROM transaction WHERE id = 10)"
cursor.execute(query)
return cursor.fetchone() is not Non
You can also test len(cursor.fetchall())

How to Capture just the value from a PostgreSQL Query

I am trying to capture the only the record from a PostgreSQL statement. The select statements outputs one row with column named as updated_at and the value is a timestamp- '2008-01-01 00:50:01'. I want to just capture/collect that value so when I call that variable, it just outputs '2008-01-01 00:50:01'.
Here is my code:
def get_etl_record():
pg_hook = PostgresHook(postgre_conn_id="post", schema='schema1')
connection = pg_hook.get_conn()
cursor = connection.cursor()
cursor2 = connection.cursor()
latest_update_query = "select max(updated_at) from my_table group by updated_at"
cursor.execute(latest_update_query)
#results= cursor.fetchall()
columns = [col[0] for col in cursor.description]
rows = [dict(zip(columns, row[0])) for row in cursor.fetchall()]
print(rows)
However this code doesnt give me an output.
Any ideas or suggestions?

There is no way to do what you want, but 3 ways to do very similar:
1.
cursor = connection.cursor()
cursor.execute(sql)
result = cursor.fetchone()
max_updated_at = result[0]
2.
dict_cur = connection.cursor(cursor_factory=psycopg2.extras.DictCursor)
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 mysql select return only first row of table, not all

im dealing with strage problem and this is like this:
this query should return all of my table:
db = MySQLdb.connect(host="localhost", port=3306, user="A", passwd="B", db="X")
cursor = db.cursor()
cursor.execute("select * from mytable")
cursor.fetchall()
for row in cursor:
print row
for loop should print all rows in cursor but it will only print the first one.
it seems cursor is filled with first row only.
is there anything that i missed here?
thanks

You need to put the output of cursor.fetchall() into a variable. Like
db = MySQLdb.connect(host="localhost", port=3306, user="A", passwd="B", db="X")
cursor = db.cursor()
cursor.execute("select * from mytable")
rows = cursor.fetchall()
for row in rows:
print row

You can try limit:
cursor.execute("select * from mytable limit 1")

Try
db = MySQLdb.connect(host="localhost", port=3306, user="A", passwd="B", db="X")
cursor = db.cursor()
for row in cursor.execute("select * from mytable"):
print row

you need a dic and save the result here
dic={}
cursor.execute("select * from table")
dic['table']=cursor.fetchall()
for row in range(len(dic['table'])):
print dic['table'][row]
and if you need print any colum
print dic['table'][row]['colum']

This is not the correct way to use the .fetchall() method. Use cursor.stored_results() and then do a fetchall() on the results to perform this task, like this:
db = MySQLdb.connect(host="localhost", port=3306, user="A", passwd="B", db="X")
cursor = db.cursor()
cursor.execute("select * from mytable")
results = cursor.stored_results()
for result in results:
print result.fetchall()

I also had this problem. My mistake was that after inserting new row in the table I didn't commit the result. So you should add db.commit() after INSERT command.

i know its been very long time since, but i didnt find this answer anywhere else and thought it might help.
cursor.execute("SELECT top 1 * FROM my_table")

How do I get tables in postgres using psycopg2?

Can someone please explain how I can get the tables in the current database?
I am using postgresql-8.4 psycopg2.

This did the trick for me:
cursor.execute("""SELECT table_name FROM information_schema.tables
WHERE table_schema = 'public'""")
for table in cursor.fetchall():
print(table)

pg_class stores all the required information.
executing the below query will return user defined tables as a tuple in a list
conn = psycopg2.connect(conn_string)
cursor = conn.cursor()
cursor.execute("select relname from pg_class where relkind='r' and relname !~ '^(pg_|sql_)';")
print cursor.fetchall()
output:
[('table1',), ('table2',), ('table3',)]

The question is about using python's psycopg2 to do things with postgres. Here are two handy functions:
def table_exists(con, table_str):
exists = False
try:
cur = con.cursor()
cur.execute("select exists(select relname from pg_class where relname='" + table_str + "')")
exists = cur.fetchone()[0]
print exists
cur.close()
except psycopg2.Error as e:
print e
return exists
def get_table_col_names(con, table_str):
col_names = []
try:
cur = con.cursor()
cur.execute("select * from " + table_str + " LIMIT 0")
for desc in cur.description:
col_names.append(desc[0])
cur.close()
except psycopg2.Error as e:
print e
return col_names

Here's a Python3 snippet that includes connect() parameters as well as generate a Python list() for output:
conn = psycopg2.connect(host='localhost', dbname='mySchema',
user='myUserName', password='myPassword')
cursor = conn.cursor()
cursor.execute("""SELECT relname FROM pg_class WHERE relkind='r'
AND relname !~ '^(pg_|sql_)';""") # "rel" is short for relation.
tables = [i[0] for i in cursor.fetchall()] # A list() of tables.

Although it has been answered by Kalu, but the query mentioned returns tables + views from postgres database. If you need only tables and not views then you can include table_type in your query like-
s = "SELECT"
s += " table_schema"
s += ", table_name"
s += " FROM information_schema.tables"
s += " WHERE"
s += " ("
s += " table_schema = '"+SCHEMA+"'"
s += " AND table_type = 'BASE TABLE'"
s += " )"
s += " ORDER BY table_schema, table_name;"
db_cursor.execute(s)
list_tables = db_cursor.fetchall()

you can use this code for python 3
import psycopg2
conn=psycopg2.connect(database="your_database",user="postgres", password="",
host="127.0.0.1", port="5432")
cur = conn.cursor()
cur.execute("select * from your_table")
rows = cur.fetchall()
conn.close()

How do I execute SQL_CALC_FOUND_ROWS in python MySQLDB

cursor.execute("SELECT SQL_CALC_FOUND_ROWS user_id FROM...limit 5")
rows = cursor.fetchall()
...
total_rows = cursor.execute("SELECT FOUND_ROWS()") #this doesn't work for some reason.
Edit: I tried SELECT FOUND_ROWS() FROM my_table...and the numbers are funky.

Seems to work here by fetching the result for the second cursor:
cursor.execute("SELECT SQL_CALC_FOUND_ROWS user_id FROM...limit 5")
rows = cursor.fetchall()
cursor.execute("SELECT FOUND_ROWS()")
(total_rows,) = cursor.fetchone()