sqlalchemy get table with a string

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table_name = "table_name"

#get table as table

new = table(**tablo)
db.session.add(table)
db.session.commit()

[Simon King]

There are lots of ways of doing this. One option is to provide a
dictionary when creating your declarative_base:

classes = {}
Base = declarative_base(class_registry=classes)

Now you can look up classes by name in that classes dictionary:

def get_table_by_name(name):
return classes[name]

Another option could be to iterate over Base.__subclasses__:

def get_table_by_name(name):
for cls in Base.__subclasses__():
if cls.__name__ == name:
return cls

Hope that helps,

Simon

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I think we keep it in RAM in the first method, so it may be a problem if the program is restarted. and I guess I don't understand what you mean by Base class.

17 Mart 2021 Çarşamba tarihinde saat 14:27:31 UTC+3 itibarıyla Simon King şunları yazdı:

[Simon King]

I assumed you were defining classes corresponding to your database
tables, as shown here:

https://docs.sqlalchemy.org/en/14/orm/tutorial.html#declare-a-mapping

If that's not how you're using SQLAlchemy, you'll have to show your code.

Simon

> To view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/1f98d725-f15f-4fde-9fe2-4205f71eb1d8n%40googlegroups.com.

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I updated sqlalchemy and now I get an error when accessing the database. And their codes need to be coded:

What I really wanted to do was add data to a table with json data in the / main / write path. but now I get an error when I send / main / new-app post request (I updated sqlalchemy and it happened) related codes are below

Sorry for taking your time, there may not be a solution. I am thinking of rewriting the codes.

from sqlalchemy import MetaData, Table, Column, Integer, String, create_engine, DateTime,VARCHAR

from flask import Flask, abort, render_template, request,session,jsonify

from flask_sqlalchemy import SQLAlchemy

from datetime import datetime

from sqlalchemy import text

import json

meta = MetaData()

engine = create_engine('sqlite:////Users/dell/Desktop/2.2/db.db')

conn = engine.connect()

app = Flask(__name__)

app.config["SQLALCHEMY_DATABASE_URI"] = 'sqlite:////Users/dell/Desktop/2.2/db.db'

db = SQLAlchemy(app)

app.secret_key = "Lbgsa,pdsa_ıda)6Kyw%61"

@app.route("/main/new-app",methods = ["GET","POST"])

def new_app():

    if request.method == "GET":

        return render_template("gg.html")

    if application.query.filter_by(name = request.form.get("username")).first():

       return "UserName..." 

    isim = request.form.get("username")

    varsayilanlar   = request.form.get("varsayilanlar")

    d_varsayilanlar = json.loads(varsayilanlar).keys()

    lis = [Column('id', Integer, primary_key = True),Column('date', DateTime, nullable=False, default=datetime.now)]

    for i in d_varsayilanlar:

        lis.append(Column(i,VARCHAR(80)))

    Table(isim, meta, *lis)

    meta.create_all(engine)

    new_app = application(name = isim,

                                password     = request.form.get("password"),

                                anaSayfa     = request.form.get("anaSayfa"),

                                manuelSayfa  = request.form.get("manuelSayfa"),

                                dinamikSayfa = request.form.get("dinamikSayfa"),

                                varsayilanlar= request.form.get("varsayilanlar"),

                                dinamik      = bool(request.form.get("dinamik")),

                                kitap        = bool(request.form.get("kitap")),

                                kalem        = bool(request.form.get("kalem")))

    db.session.add(new_app)

    db.session.commit()

    return "200OK"

@app.route("/main/write",methods = ["GET","POST"])

def write():

    if request.method == "GET":

        return "POST!"

    app = application.query.filter_by(name = request.form.get("username")).first()

    if not (app):

       return "Uygulama Bulunamadı"

    elif not(app.kalem) and (app.password != request.form.get("password")):

        return "TABLE NOT FOUND"

    tablo = json.loads(request.form.get("varsayilanlar"))

#i want to get table here

    new_row = meta.tables[request.form.get("username")]

    employee = new_row(**tablo)

    db.session.add(employee)

    db.session.commit()

    return "200ok"

class application(db.Model):

    id           = db.Column(db.Integer,primary_key = True)

    name         = db.Column(db.String(80))

    password     = db.Column(db.String(80))

    anaSayfa     = db.Column(db.String(80))

    manuelSayfa  = db.Column(db.String(80))

    dinamik      = db.Column(db.String(80))

    dinamikSayfa = db.Column(db.String(80))

    varsayilanlar= db.Column(db.String(80))

    kitap        = db.Column(db.String(80))

    kalem        = db.Column(db.String(80))

    pub_date     = db.Column(db.DateTime, nullable=False,default=datetime.now)

17 Mart 2021 Çarşamba tarihinde saat 17:17:56 UTC+3 itibarıyla Simon King şunları yazdı:

[Simon King]

OK, I see. You're creating tables dynamically, and you want to be able
to insert data into those tables.

I think it'll be easier to use SQLAlchemy Core for this, rather than
the ORM. You can use reflection to load table definitions from the
database.

https://docs.sqlalchemy.org/en/14/core/reflection.html#reflecting-database-objects
https://docs.sqlalchemy.org/en/14/core/tutorial.html#coretutorial-insert-expressions

That would look something like this (completely untested):

# if there's a chance multiple people can call this
# at the same time, you'll need to add a lock around it
def get_table(table_name):
if table_name in meta.tables:
return meta.tables[table_name]
return Table(table_name, meta, autoload_with=db.session.connection())

table_name = request.form.get("varsayilanlar")
table = get_table(table_name)
insert = table.insert().values(**tablo)
db.session.execute(insert)

Simon

> To view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/20c81613-0794-4909-b353-200446d0a8a1n%40googlegroups.com.

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Thank you for your response and I am immediately interested in your articles.

17 Mart 2021 Çarşamba tarihinde saat 20:46:11 UTC+3 itibarıyla Simon King şunları yazdı: