Develop Reference

pymysql and BEFORE INSERT trigger problem

I have a DB table which looks like
CREATE TABLE `localquotes` (
`id` bigint NOT NULL AUTO_INCREMENT,
`createTime` timestamp(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
`tag` varchar(8) NOT NULL,
`monthNum` int NOT NULL,
`flag` float NOT NULL DEFAULT '0',
`optionType` varchar(1) NOT NULL,
`symbol` varchar(30) NOT NULL,
`bid` float DEFAULT NULL,
`ask` float DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=15 DEFAULT CHARSET=utf8 COLLATE=utf8_general_ci;
for which one I have created a trigger
CREATE DEFINER=`user`#`localhost` TRIGGER `localquotes_BEFORE_INSERT` BEFORE INSERT ON `localquotes` FOR EACH ROW BEGIN
SET new.tag=left(symbol,3);
SET new.monthNum=right(left(symbol,5),1);
SET new.optionType=left(right(symbol,11),1);
SET new.flag=right(left(symbol,11),4);
END
which is causing pymysql.err.OperationalError: (1054, "Unknown column 'symbol' in 'field list'") for pymysql on simple INSERT like
insertQuery = "INSERT INTO localquotes (tag,monthNum,flag,optionType,symbol,bid) VALUES (%s,%s,%s,%s,%s,%s)"
insertValues = ('UNKNOWN', d.strftime("%m"), 0, 'X', symbol, bid)
cursor.execute(insertQuery, insertValues)
db.commit()
When I will remove that trigger insert works fine.
Any clue why code is complaining about symbol column, which exists, when there is trigger set for that column value from the insert request?

You must reference all the columns of the row that spawned the trigger with the NEW.* prefix.
SET new.tag=left(new.symbol,3);
And so on.

stored procedure call from sqlalchemy not commit

I have tested my SP in MySQL and it works fine. I was able to insert new entry with it. I try to call it from flask with alchemy and it does run, but insert is not made into the table although it appears to execute the right commands.
My SP checks if there is an existing entry if yes then return 0, if no then insert the entry and return 1. When I send a new query from backend, I got 1 as return value but insert is not made in the table, When I send the same query, the return value is still 1. When I send an existing query that the table holds, the return value is 0.
I have other routes with the same db.connect() and it does fetch information. I read other posts about calling SP with the same execute function to run raw sql. From the doc it does seem execute doesn't require extra commit command to confirm the transaction.
So why can't I insert from the flask server?
This is the backend function
def add_book(info):
try:
connection = db.connect()
title = info['bookTitle']
url = info['bookUrl']
isbn = info['isbn']
author = info['author']
#print("title: " + title + " url: "+ url + " isbn: "+ str(isbn) + " author"+ str(author))
query = 'CALL add_book("{}", "{}", {}, {});'.format(title, url, isbn, author)
#print(query)
query_results = connection.execute(query)
connection.close()
query_results = [x for x in query_results]
result = query_results[0][0]
except Exception as err:
print(type(err))
print(err.args)
return result
This is the table to insert
CREATE TABLE `book` (
`isbn` int(11) DEFAULT NULL,
`review_count` int(11) DEFAULT NULL,
`language_code` varchar(10) DEFAULT NULL,
`avg_rating` int(11) DEFAULT NULL,
`description_text` text,
`formt` varchar(30) DEFAULT NULL,
`link` varchar(200) DEFAULT NULL,
`authors` int(11) DEFAULT NULL,
`publisher` varchar(30) DEFAULT NULL,
`num_pages` int(11) DEFAULT NULL,
`publication_month` int(11) DEFAULT NULL,
`publication_year` int(11) DEFAULT NULL,
`url` varchar(200) DEFAULT NULL,
`image_url` varchar(200) DEFAULT NULL,
`book_id` int(11) NOT NULL AUTO_INCREMENT,
`ratings_count` int(11) DEFAULT NULL,
`work_id` int(11) DEFAULT NULL,
`title` varchar(200) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
PRIMARY KEY (`book_id`),
KEY `authors` (`authors`),
CONSTRAINT `book_ibfk_2` FOREIGN KEY (`authors`) REFERENCES `author` (`author_id`) ON DELETE RESTRICT ON UPDATE CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=36485537 DEFAULT CHARSET=utf8;
This is the SP
DELIMITER $$
CREATE DEFINER=`root`#`%` PROCEDURE `add_book`(
IN titleIn VARCHAR(200), urlIn VARCHAR(200), isbnIn INT, authorIn INT)
BEGIN
DECLARE addSucess INT;
DECLARE EXIT HANDLER FOR sqlexception
BEGIN
GET diagnostics CONDITION 1
#p1 = returned_sqlstate, #p2 = message_text;
SELECT #pa1, #p2;
ROLLBACK;
END;
DECLARE exit handler for sqlwarning
BEGIN
GET DIAGNOSTICS CONDITION 1
#p1 = RETURNED_SQLSTATE, #p2 = MESSAGE_TEXT;
SELECT #p1 as RETURNED_SQLSTATE , #p2 as MESSAGE_TEXT;
ROLLBACK;
END;
IF EXISTS (SELECT 1 FROM book WHERE title = titleIn) THEN
SET addSucess = 0;
ELSE
INSERT INTO book (authors, title, url, book_id)
VALUES (authorIn, titleIn, urlIn, null);
SET addSucess = 1;
END IF;
SELECT addSucess;
END$$
DELIMITER ;
My user permission from show grants for current_user
[('GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, RELOAD, SHUTDOWN, PROCESS, REFERENCES, INDEX, ALTER, SHOW DATABASES, CREATE TEMPORARY TABLES, LOC ... (73 characters truncated) ... OW VIEW, CREATE ROUTINE, ALTER ROUTINE, CREATE USER, EVENT, TRIGGER, CREATE TABLESPACE, CREATE ROLE, DROP ROLE ON *.* TO `root`#`%` WITH GRANT OPTION',), ('GRANT APPLICATION_PASSWORD_ADMIN,CONNECTION_ADMIN,ROLE_ADMIN,SET_USER_ID,XA_RECOVER_ADMIN ON *.* TO `root`#`%` WITH GRANT OPTION',), ('REVOKE INSERT, UPDATE, DELETE, CREATE, DROP, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, CREATE VIEW, CREATE ROUTINE, ALTER ROUTINE ON `mysql`.* FROM `root`#`%`',), ('REVOKE INSERT, UPDATE, DELETE, CREATE, DROP, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, CREATE VIEW, CREATE ROUTINE, ALTER ROUTINE ON `sys`.* FROM `root`#`%`',), ('GRANT INSERT ON `mysql`.`general_log` TO `root`#`%`',), ('GRANT INSERT ON `mysql`.`slow_log` TO `root`#`%`',), ('GRANT `cloudsqlsuperuser`#`%` TO `root`#`%`',)]

I solved it with the Session api instead. If someone is reading, pls tell me a better way of passing the params and parse the return result
def add_book(info):
title = info['bookTitle']
url = info['bookUrl']
isbn = info['isbn']
author = info['author']
with Session(db) as session:
session.begin()
try:
query = 'CALL insert_book("{}", "{}", {}, {});'.format(title, url, isbn, author)
result = session.execute(text(query)).all()
except:
session.rollback()
raise
else:
session.commit()

Mysql insert lock wait timeout exceeded - auto increment

I'm having an issue with my application causing MySQL table to be locked due to inserts which take a long time, after reviewing online articles, it seems like it's related to auto increment, info below -
Python that inserts data (row at a time unfortunately as I need the auto incremented id for reference in future inserts) -
for i, flightobj in stats[ucid]['flight'].items():
flight_fk = None
# Insert flights
try:
with mysqlconnection.cursor() as cursor:
sql = "insert into cb_flights(ucid,takeoff_time,end_time,end_event,side,kills,type,map_fk,era_fk) values(%s,%s,%s,%s,%s,%s,%s,%s,%s);"
cursor.execute(sql, (
ucid, flightobj['start_time'], flightobj['end_time'], flightobj['end_event'], flightobj['side'],
flightobj['killnum'], flightobj['type'], map_fk, era_fk))
mysqlconnection.commit()
if cursor.lastrowid:
flight_fk = cursor.lastrowid
else:
flight_fk = 0
except pymysql.err.ProgrammingError as e:
logging.exception("Error: {}".format(e))
except pymysql.err.IntegrityError as e:
logging.exception("Error: {}".format(e))
except TypeError as e:
logging.exception("Error: {}".format(e))
except:
logging.exception("Unexpected error:", sys.exc_info()[0])
The above runs every 2 minutes on the same data and is supposed to insert only non duplicates as the MySQL would deny duplicates due to the unique ucid_takeofftime index.
MYSQL info, cb_flights table -
`pk` int(11) NOT NULL AUTO_INCREMENT,
`ucid` varchar(50) NOT NULL,
`takeoff_time` datetime DEFAULT NULL,
`end_time` datetime DEFAULT NULL,
`end_event` varchar(45) DEFAULT NULL,
`side` varchar(45) DEFAULT NULL,
`kills` int(11) DEFAULT NULL,
`type` varchar(45) DEFAULT NULL,
`map_fk` int(11) DEFAULT NULL,
`era_fk` int(11) DEFAULT NULL,
`round_fk` int(11) DEFAULT NULL,
PRIMARY KEY (`pk`),
UNIQUE KEY `ucid_takeofftime` (`ucid`,`takeoff_time`),
KEY `ucid_idx` (`ucid`) /*!80000 INVISIBLE */,
KEY `end_event` (`end_event`) /*!80000 INVISIBLE */,
KEY `side` (`side`)
) ENGINE=InnoDB AUTO_INCREMENT=76023132 DEFAULT CHARSET=utf8;
Now inserts into the table from the Python code, can take sometimes over 60 seconds.
I beleive it might be related to the auto increment that is creating the lock on the table, if so, I'm looking for a workaround.
innodb info -
innodb_autoinc_lock_mode 2
innodb_lock_wait_timeout 50
buffer is used up to 70% more or less.
Appreciate any assistance with this, either from application side or MySQL side.
EDIT
Adding the create statement for the cb_kills table which is also used with inserts but without an issue as far as I can see, this is in response to the comment on the 1st answer.
CREATE TABLE `cb_kills` (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`time` datetime DEFAULT NULL,
`killer_ucid` varchar(50) NOT NULL,
`killer_side` varchar(10) DEFAULT NULL,
`killer_unit` varchar(45) DEFAULT NULL,
`victim_ucid` varchar(50) DEFAULT NULL,
`victim_side` varchar(10) DEFAULT NULL,
`victim_unit` varchar(45) DEFAULT NULL,
`weapon` varchar(45) DEFAULT NULL,
`flight_fk` int(11) NOT NULL,
`kill_id` int(11) NOT NULL,
PRIMARY KEY (`pk`),
UNIQUE KEY `ucid_killid_flightfk_uniq` (`killer_ucid`,`flight_fk`,`kill_id`),
KEY `flight_kills_fk_idx` (`flight_fk`),
KEY `killer_ucid_fk_idx` (`killer_ucid`),
KEY `victim_ucid_fk_idx` (`victim_ucid`),
KEY `time_ucid_killid_uniq` (`time`,`killer_ucid`,`kill_id`),
CONSTRAINT `flight_kills_fk` FOREIGN KEY (`flight_fk`) REFERENCES `cb_flights` (`pk`)
) ENGINE=InnoDB AUTO_INCREMENT=52698582 DEFAULT CHARSET=utf8;

You can check if autocommit is set to 1, this forces to commit every row and disabling it makes it somewhat faster
Instead of committing every insert try to bulk insert.
For that you should check
https://dev.mysql.com/doc/refman/8.0/en/optimizing-innodb-bulk-data-loading.html
and do something like
data = [
('city 1', 'MAC', 'district 1', 16822),
('city 2', 'PSE', 'district 2', 15642),
('city 3', 'ZWE', 'district 3', 11642),
('city 4', 'USA', 'district 4', 14612),
('city 5', 'USA', 'district 5', 17672),
]
sql = "insert into city(name, countrycode, district, population)
VALUES(%s, %s, %s, %s)"
number_of_rows = cursor.executemany(sql, data)
db.commit()

I want to put in here some of the ways I worked on finding a solution to this problem. I'm not an expert in MySQL but I think these steps can help anyone looking to find out why he has lock wait timeouts.
So the troubleshooting steps I took are as follows -
1- Check if I can find in the MySQL slow log the relevant query that is locking my table. Usually it's possible to find queries that run a long time and also locks with the info below and the query right after it
# Time: 2020-01-28T17:31:48.634308Z
# User#Host: # localhost [::1] Id: 980397
# Query_time: 250.474040 Lock_time: 0.000000 Rows_sent: 10 Rows_examined: 195738
2- The above should give some clue on what's going on in the server and what might be waiting for a long time. Next I ran the following 3 queries to identify what is in use:
check process list on which process are running -
show full processlist;
check tables in use currently -
show open tables where in_use>0;
check running transactions -
SELECT * FROM `information_schema`.`innodb_trx` ORDER BY `trx_started`;
3- The above 2 steps should give enough information on which query is locking the tables. in my case here I had a SP that ran an insert into <different table> select from <my locked table>, while it was inserting to a totally different table, this query was locking my table due to the select operation that took a long time.
To work around it, I changed the SP to work with temporary tables and now although the query is still not completely optimized, there are no locks on my table.
Adding here how I run the SP on temporary tables for async aggregated updates.
CREATE DEFINER=`username`#`%` PROCEDURE `procedureName`()
BEGIN
drop temporary table if exists scheme.temp1;
drop temporary table if exists scheme.temp2;
drop temporary table if exists scheme.temp3;
create temporary table scheme.temp1 AS select * from scheme.live1;
create temporary table scheme.temp2 AS select * from scheme.live2;
create temporary table scheme.temp3 AS select * from scheme.live3;
create temporary table scheme.emptytemp (
`cName1` int(11) NOT NULL,
`cName2` varchar(45) NOT NULL,
`cName3` int(11) NOT NULL,
`cName4` datetime NOT NULL,
`cName5` datetime NOT NULL,
KEY `cName1` (`cName1`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
INSERT into scheme.emptytemp
select t1.x,t2.y,t3.z
from scheme.temp1 t1
JOIN scheme.temp2 t2
ON t1.x = t2.x
JOIN scheme.temp3 t3
ON t2.y = t3.y
truncate table scheme.liveTable;
INSERT into scheme.liveTable
select * from scheme.emptytemp;
END
Hope this helps anyone that encounters this issue

sqlite3.OperationalError: no such table: main.source

I am making an API that uses Python Flask and Sqlite3. Most of it works. Specifically:
all GET endpoints/SELECT queries work
two POST endpoints/INSERT INTO queries work
However, the remaining POSTs/INSERT INTOs do not work. They all have the same sqlite3.OperationalError with the message:
no such table: main.source
This is weird because none of the queries use a table called "source" or "main.source". I print the queries before I execute them, and I have tried copy/pasting the queries into the sqlite3 command prompt. The queries have no issues when I do that.
The other weird thing is that all the INSERT INTO queries call the same function to create the actual query (which in turn calls the function to run queries ... used by ALL queries most of which work). Only some of the INSERT INTOs cause this error.
Some potentially useful information:
An excerpt from createdb.sql
CREATE TABLE transactions (
id INTEGER PRIMARY KEY,
buyer INTEGER NOT NULL,
seller INTEGER NOT NULL,
amount INTEGER NOT NULL,
currency VARCHAR(6) NOT NULL,
fee INTEGER NOT NULL,
source INTEGER NOT NULL,
description TEXT NOT NULL,
status VARCHAR(40) NOT NULL,
created TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
);
The insert into that Python prints/that throws an error in execute:
INSERT INTO transactions (status, fee, description, source, seller, currency, amount, buyer) VALUES ('initiated', '1', 'nada', '1', '2', 'USD', '1000', '1');
And some stuff from Sqlite's prompt:
sqlite> .tables
conversations sources users
messages transactions withdrawals
sqlite> SELECT id, description FROM transactions;
1|hella mulah
2|payback
3|woohoo
sqlite> INSERT INTO transactions (status, fee, description, source, seller, currency, amount, buyer) VALUES ('initiated', '1', 'nada', '1', '2', 'USD', '1000', '1');
sqlite>
sqlite> SELECT id, description FROM transactions;
1|hella mulah
2|payback
3|woohoo
4|nada
For references, here is a POST command that has no error despite using most of the same stuff:
INSERT INTO users (session, balance, name, firebaseToken) VALUES ('ABCDEFG', '0', 'Mr Miyagi', 'ABCDEFG');
There are a lot of similar questions on SO but here's why they are not duplicates:
flask/sqlalchemy - OperationalError: (sqlite3.OperationalError) no such table Yes, I created the tables before using them.
Why am I suddenly getting "OperationalError: no such table"? my Flask app is able to find the database no problem (and most of the queries work without a hitch). To be safe I made my DB in connect an absolute path. No effect.
Error: sqlite3.OperationalError: no such table: main.m I don't do any weird indexing + if I did this the copy pasting wouldn't work
Python Sqlite3 - Data is not saved permanently: I do call commit in #app.teardown_appcontext. I also tried calling commit after every query. No effect.
Other stuff I considered but ruled out:
There is a list of disallowed names, but these are not included http://www.sqlite.org/lang_keywords.html. transactions is close to transaction but not the same. source is not on the list.
I'm sure this will end up being some kind of silly messup but any ideas on where to look would be much appreciated. I also tried Googling this error but I didn't see anything helpful.
--- more code ---
This is database.py
import sqlite3
import flask
import backend
def dict_factory(cursor, row):
output = {}
for idx, col in enumerate(cursor.description):
output[col[0]] = row[idx]
return output
def get_db():
if not hasattr(flask.g, 'sqlite_db'):
flask.g.sqlite_db = sqlite3.connect("/my/absolute/path/var/data.db"
)
flask.g.sqlite_db.row_factory = dict_factory
flask.g.sqlite_db.execute("PRAGMA foreign_keys = ON;")
return flask.g.sqlite_db
def query(query, args=(), islast=False):
print(query) # this is where the print from before is
cur = get_db().execute(query, args)
rowvector = cur.fetchall()
if islast:
cur.close()
return rowvector
#backend.app.teardown_appcontext
def close_db(error):
if hasattr(flask.g, 'sqlite_db'):
flask.g.sqlite_db.commit()
flask.g.sqlite_db.close()
This is selected sections from apiimpl.py
QUERY_INSERT = "INSERT INTO"
QUERY_SELECT = "SELECT"
QUERY_UPDATE = "UPDATE"
def queryhelper(*args, **kwargs):
sqltxt = None
selectstr = None
if kwargs["action"] == QUERY_INSERT:
sqltxt = "{} {} ({}) VALUES ({});".format(
QUERY_INSERT,
kwargs["table"],
", ".join(["{}".format(x) for x in kwargs["cols"]]),
", ".join(["'{}'".format(x) for x in kwargs["vals"]]),
)
# pretty sure this next bit is not relevant but here it is anyway
selectstr = "SELECT * FROM {} WHERE ROWID=(SELECT last_insert_rowid());".format(
kwargs["table"],
)
elif kwargs["action"] == QUERY_SELECT:
# not relevant
elif kwargs["action"] == QUERY_UPDATE:
# not relevant
else:
assert(kwargs["action"] in [QUERY_INSERT, QUERY_SELECT, QUERY_UPDATE,])
try:
rv = db.query(sqltxt) # this is where the error is thrown
if selectstr:
return db.query(selectstr)
else:
return rv
except sqlite3.OperationalError as e:
# this is where the error is caught
return api_error("SQL error (1): {}", str(e), code=500)
def append(tablename, args):
tabledata = TABLES().tablenamemap[tablename]
print("tablename: " + tablename) # "tablename: transactions"
# a bunch of error detection
rv = queryhelper(
action=QUERY_INSERT,
table=tablename,
cols=args.keys(),
vals=args.values(),
)
# not shown: potentially returning json.dumps(rv)
return rv
def transactions_post(req):
# a lot of stuff to turn req into validargs
# printed validargs: {'status': 'initiated', u'fee': u'1', u'description': u'nada', u'source': u'1', u'seller': u'2', u'currency': u'USD', u'amount': u'1000', u'buyer': u'1'}
return append("transactions", validargs)
#backend.app.route("/transactions", methods=["GET", "POST", "PUT"])
def transactions_route():
return {
"GET": transactions_get, # get list of transactions
"POST": transactions_post, # initiate a transaction
"PUT": transactions_put, # change transaction status
}[flask.request.method](flask.request)
P.S. the purpose of this question is not to discuss the implementation, but if you want to leave a comment that's ok with me.
--- in response to comment --
sqlite> SELECT * FROM sqlite_master WHERE type="table" AND name="transactions";
table|transactions|transactions|4|CREATE TABLE transactions (
id INTEGER PRIMARY KEY,
buyer INTEGER NOT NULL,
seller INTEGER NOT NULL,
amount INTEGER NOT NULL,
currency VARCHAR(6) NOT NULL,
fee INTEGER NOT NULL,
source INTEGER NOT NULL,
description TEXT NOT NULL,
status VARCHAR(40) NOT NULL,
created TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
FOREIGN KEY (buyer) REFERENCES users(id), -- do not want to delete on CASCADE
FOREIGN KEY (seller) REFERENCES users(id), -- do not want to delete on CASCADE
FOREIGN KEY (source) REFERENCES source(id) -- do not want to delete on CASCADE
)

It looks like you are referencing a table that doesn't exist based on your .tables command.
sqlite> .tables
conversations sources users
messages transactions withdrawals
And this create table statement.
CREATE TABLE transactions (
id INTEGER PRIMARY KEY,
buyer INTEGER NOT NULL,
seller INTEGER NOT NULL,
amount INTEGER NOT NULL,
currency VARCHAR(6) NOT NULL,
fee INTEGER NOT NULL,
source INTEGER NOT NULL,
description TEXT NOT NULL,
status VARCHAR(40) NOT NULL,
created TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
FOREIGN KEY (buyer) REFERENCES users(id), -- do not want to delete on CASCADE
FOREIGN KEY (seller) REFERENCES users(id), -- do not want to delete on CASCADE
FOREIGN KEY (source) REFERENCES source(id) -- do not want to delete on CASCADE
-- ^ there is no source table
)
If you change source(id) to sources(id) you should be good.

MySQL datetime column WHERE col IS NULL fails

I cannot get my very basic SQL query to work as it returns 0 values despite the fact that there are clearly nulls
query
SELECT
*
FROM
leads AS l
JOIN closes c ON l.id = c.lead_id
WHERE
c.close_date IS NULL
DDL
CREATE TABLE closes
(
id INT AUTO_INCREMENT
PRIMARY KEY,
lead_id INT NOT NULL,
close_date DATETIME NULL,
close_type VARCHAR(255) NULL,
primary_agent VARCHAR(255) NULL,
price FLOAT NULL,
gross_commission FLOAT NULL,
company_dollar FLOAT NULL,
address VARCHAR(255) NULL,
city VARCHAR(255) NULL,
state VARCHAR(10) NULL,
zip VARCHAR(10) NULL,
CONSTRAINT closes_ibfk_1
FOREIGN KEY (lead_id) REFERENCES leads (id)
)
ENGINE = InnoDB;
CREATE INDEX lead_id
ON closes (lead_id);
I should mention that I am inserting the data with a python web scraper and SQLAlchemy. If the data is not scraped it will be None on insert.
Here is a screenshot of datagrip showing a null value in the row
EDIT
Alright so I went ahead and ran the following on some of the entries in the table where the value was already <null>
UPDATE closes
SET close_date = NULL
WHERE
lead_id = <INTEGERVAL>
;
What is interesting now is that when running the original query I do actually return the 2 records that I ran the update query for (the expected outcome). This would lead me to believe that the issues is with how my SQLAlchemy model is mapping the values on insert.
models.py
class Close(db.Model, ItemMixin):
__tablename__ = 'closes'
id = db.Column(db.Integer, primary_key=True)
lead_id = db.Column(db.Integer, db.ForeignKey('leads.id'), nullable=False)
close_date = db.Column(db.DateTime)
close_type = db.Column(db.String(255))
primary_agent = db.Column(db.String(255))
price = db.Column(db.Float)
gross_commission = db.Column(db.Float)
company_dollar = db.Column(db.Float)
address = db.Column(db.String(255))
city = db.Column(db.String(255))
state = db.Column(db.String(10))
zip = db.Column(db.String(10))
def __init__(self, item):
self.build_from_item(item)
def build_from_item(self, item):
for k, v in item.items():
setattr(self, k, v)
But I am fairly confident the value is a python None in the event no value is scraped from the website. My understanding is that SQLAlchemy would map a None to NULL on insert and given that nullable=True is the default setting, which can seen on the generated DDL, I am still at a loss as to why it appears to be NULL when in reality it is not behaving that way.
EDIT 2
Only place where I think the issue would be happening is where my spider actually scrapes the data and assigns it to the Item which is shown below
closes.py
# item['close_date'] = None at this point
try:
item['close_date'] = arrow.get(item['close_date'], 'MMM D, YYYY').format('YYYY-MM-DD')
except ParserError as e:
# Maybe item['close_date'] = None here?
spider.logger.error(f'Parse error: {item["close_date"]} - {e}')
In the python code I've written this would appear to be the place where the issue would arise. But if arrow.get throws an exception the value of item['close_date'] should still be None. If that is not the case and even if it is it does not explain why it appears that the record value is NULL even thought it does not behave like it is.

I'm guessing that you're having an issue with the join, not the NULL value. The query below returns 1 result for me. More info about your data, the software used for querying (I tested with SQL Yog), and applicable versions might help.
EDIT
It could be that you're having issues with MySQL's 'zero date'.
https://dev.mysql.com/doc/refman/5.7/en/date-and-time-types.html
MySQL permits you to store a “zero” value of '0000-00-00' as a “dummy
date.” This is in some cases more convenient than using NULL values,
and uses less data and index space. To disallow '0000-00-00', enable
the NO_ZERO_DATE mode.
I've updated the SQL data below to include a zero date in the INSERT and SELECT's WHERE.
DROP TABLE IF EXISTS closes;
DROP TABLE IF EXISTS leads;
CREATE TABLE leads (
id INT(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (id)
) ENGINE=INNODB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;
INSERT INTO leads(id) VALUES (1),(2),(3);
CREATE TABLE closes (
id INT(11) NOT NULL AUTO_INCREMENT,
lead_id INT(11) NOT NULL,
close_date DATETIME DEFAULT NULL,
close_type VARCHAR(255) DEFAULT NULL,
primary_agent VARCHAR(255) DEFAULT NULL,
price FLOAT DEFAULT NULL,
gross_commission FLOAT DEFAULT NULL,
company_dollar FLOAT DEFAULT NULL,
address VARCHAR(255) DEFAULT NULL,
city VARCHAR(255) DEFAULT NULL,
state VARCHAR(10) DEFAULT NULL,
zip VARCHAR(10) DEFAULT NULL,
PRIMARY KEY (id),
KEY lead_id (lead_id),
CONSTRAINT closes_ibfk_1 FOREIGN KEY (lead_id) REFERENCES leads (id)
) ENGINE=INNODB AUTO_INCREMENT=4 DEFAULT CHARSET=latin1;
INSERT INTO closes(id,lead_id,close_date,close_type,primary_agent,price,gross_commission,company_dollar,address,city,state,zip)
VALUES
(1,3,'0000-00-0000',NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL),
(2,1,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL),
(3,2,'2018-01-09 17:01:44',NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);
SELECT
*
FROM
leads AS l
JOIN closes c ON l.id = c.lead_id
WHERE
c.close_date IS NULL OR c.close_date = '0000-00-00';