def _get_cursor(self):
try:
if self.connection is None:
self.connection = mysql.connect(**self.connection_params)
else:
self.connection.ping(reconnect=True)
cur = self.connection.cursor()
cur.execute('SELECT VERSION()')
if not cur.fetchall():
raise BackendError("_get_cursor: Connection Failed")
cur.reset()
return cur
except Exception as ex:
raise BackendError("_get_cursor: "+str(ex))
def __init__(self, connection_params):
connection_params["server"] = connection_params.pop("host", None)
for key in list(connection_params):
if connection_params[key] is None:
del connection_params[key]
super().__init__(connection_params)
try:
self.connection = pymssql.connect(login_timeout=5, **connection_params)
except pymssql.Error as ex:
raise BackendError(str(ex)) from ex
except ValueError:
# ValueError is raised when 'server' contains "\\"
raise BackendError("Incorrect format of connection details")
def execute_sql_query(self, query, params=()):
try:
with self.connection.cursor() as cur:
cur.execute(query, *params)
yield cur
except pymssql.Error as ex:
raise BackendError(str(ex)) from ex
def count_approx(self, query):
with self.connection.cursor() as cur:
try:
cur.execute("SET SHOWPLAN_XML ON")
try:
cur.execute(query)
result = cur.fetchone()
match = self.EST_ROWS_RE.search(result[0])
if not match:
# Either StatementEstRows was not found or
# a float is received.
# If it is a float then it is most probable
# that the server's statistics are out of date
# and the result is false. In that case
# it is preferable to return None so
# an exact count be used.
return None
return int(match.group(1))
finally:
cur.execute("SET SHOWPLAN_XML OFF")
except pymssql.Error as ex:
if "SHOWPLAN permission denied" in str(ex):
warnings.warn(
"SHOWPLAN permission denied, count approximates will not be used"
)
return None
raise BackendError(str(ex)) from ex
def count_approx(self, query):
with self.connection.cursor() as cur:
try:
cur.execute("SET SHOWPLAN_XML ON")
try:
cur.execute(query)
result = cur.fetchone()
return int(self.EST_ROWS_RE.search(result[0]).group(1))
except AttributeError:
# This is to catch a bug from SQL Server 2012
# (the StatementEstRows=float instead of an int)
pass
finally:
cur.execute("SET SHOWPLAN_XML OFF")
except pymssql.Error as ex:
if "SHOWPLAN permission denied" in str(ex):
warnings.warn(
"SHOWPLAN permission denied, count approximates will not be used"
)
return None
raise BackendError(str(ex)) from ex
# In case of an AttributeError, give a second chance:
# Use the long method for counting (or upgrade SQL Server version :) )
cur.execute("SELECT count(*) FROM ( {} ) x".format(query))
result = cur.fetchone()
return result[0]
def __init__(self, connection_params):
connection_params["server"] = connection_params.pop("host", None)
for key in list(connection_params):
if connection_params[key] is None:
del connection_params[key]
super().__init__(connection_params)
try:
self.connection = pymssql.connect(**connection_params)
except pymssql.Error as ex:
raise BackendError(str(ex)) from ex
def __init__(self, connection_params):
super().__init__(connection_params)
connection_params.pop('port')
self.connection_params = connection_params
try:
cursor = self._get_cursor()
cursor.execute('SELECT VERSION()')
if cursor.fetchall() is None:
raise BackendError
cursor.close()
except Exception as e:
raise BackendError(str(e))
def execute_sql_query(self, query, params=None):
connection = self.connection_pool.getconn()
cur = connection.cursor()
try:
utfquery = cur.mogrify(query, params).decode('utf-8')
log.debug("Executing: %s", utfquery)
t = time()
cur.execute(query, params)
yield cur
log.info("%.2f ms: %s", 1000 * (time() - t), utfquery)
except (Error, ProgrammingError) as ex:
raise BackendError(str(ex)) from ex
finally:
connection.commit()
self.connection_pool.putconn(connection)
def count_approx(self, query):
try:
with self.connection.cursor() as cur:
cur.execute("SET SHOWPLAN_XML ON")
try:
cur.execute(query)
result = cur.fetchone()
return int(self.EST_ROWS_RE.search(result[0]).group(1))
finally:
cur.execute("SET SHOWPLAN_XML OFF")
except pymssql.Error as ex:
if "SHOWPLAN permission denied" in str(ex):
warnings.warn("SHOWPLAN permission denied, count approximates will not be used")
return None
raise BackendError(str(ex)) from ex
def __init__(self, connection_params):
super().__init__(connection_params)
raise BackendError("Error connecting to DB.")
def _create_connection_pool(self):
try:
self.connection_pool = ThreadedConnectionPool(
1, 16, **self.connection_params)
except Error as ex:
raise BackendError(str(ex)) from ex
