CODEWITHSUNDEEP
pythonsqlalchemy
anon_swe
anon_swe

Reputation: 9345

SQLAlchemy: Difficulty Querying my DB

I'm writing a small Python script / app and am just getting my feet wet with SQLAlchemy. The only class I have is "Player", which is defined as follows:

class Player:
    def __init__(self,  rating, college, ranking = None, firstName = None, lastName = None):
        self.rating = rating
        self.college = college
        self.ranking = ranking
        self.firstName = firstName
        self.lastName = lastName

Now I have a module called databaseFunctions.py and within it I have these two functions:

#if player exists, update his rating and ranking; otherwise, add new object to DB
def updateSpecificDBEntry(playerObject, session):
    #find player in DB with firstName and lastName
    currentPlayer = session.query(Player).filter(firstName == playerObject.firstName).filter(playerObject.lastName == lastName).first()
    #set rating = newRating
    if currentPlayer.count():
        currentPlayer.rating = playerObject.rating
        currentPlayer.ranking = playerObject.ranking
    else:
        addEntryToDB(playerObject, session)

def updateEntireDB(arrayOfPlayerObjects, session):
    for player in arrayOfPlayerObjects:
        updateSpecificDBEntry(player, session)

Here's what my main method looks like:

def main():
    #create engine (for use by base and session)
    engine = databaseFunctions.createEngine()
    #create session
    session = databaseFunctions.createSession(engine)
    #get all players from CSA website
    allPlayers = getSortedGender(constants.mainURL, constants.menTeams)
    databaseFunctions.updateEntireDB(allPlayers, session)

My code actually works up until the last function call. At this point, I get the following error:

  File "helpfulFunctions.py", line 114, in <module>
    main()
  File "helpfulFunctions.py", line 107, in main
    databaseFunctions.updateEntireDB(allPlayers, session)
  File "/Users/benjaminclayman/Desktop/SquashScraper/databaseFunctions.py", line 42, in updateEntireDB
    updateSpecificDBEntry(player, session)
  File "/Users/benjaminclayman/Desktop/SquashScraper/databaseFunctions.py", line 32, in updateSpecificDBEntry
    currentPlayer = session.query(Player).filter(firstName == playerObject.firstName).filter(playerObject.lastName == lastName).first()
NameError: global name 'firstName' is not defined

I'm a bit confused because I'm querying all Player objects in the DB for entries whose first names match the firstName of the passed in playerObject and whose last names match the lastName of the passed in playerObject.

Any idea why I'm getting this error?

I initially called this function in main() but wasn't using it so took it out:

def createBase(engine):  
    Base = declarative_base()
    Base.metadata.create_all(engine)
    return Base

As in, I was saying:

Base = databaseFunctions.createBase(engine)

And then doing nothing with Base. Not sure if this is part of the issue.

Thanks for the help, bclayman

Upvotes: 2

Views: 111

Answers (1)

otherchirps
otherchirps

Reputation: 1846

In your updateSpecificDBEntry filter, you have:

.filter(firstName == playerObject.firstName)

The variable "firstName" doesn't exist.

It looks like you meant something like:

currentPlayer = session.query(Player).filter(Player.firstName == playerObject.firstName).filter(playerObject.lastName == Player.lastName).first()

So you're filtering a Player column, against the given playerObject attribute.

Upvotes: 2

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