Category "database"

JDBC Derby driver not found

I've followed the JDBC tutorial at: http://docs.oracle.com/javase/tutorial/jdbc/basics/gettingstarted.html, and managed to build and create my own JDBC database

Unable to connect to Azure Database from a web app deployed on Azure App Services account

I deployed a web app on Azure App Services. When web app tries to connect to the Azure SQL Database connection failed. I downloaded the event log from Kudu, I f

Is tagging a form of data mining?

I am implementing a small CRM system. and the concept of data mining to predict and find opportunities and trends are essential for such systems. One data minin

django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb

The problem Im facing while trying to connect to database for mysql. I have also given the database settings that i have used. Traceback (most recent call las

how to make my own auto increment in php?

The in-built Auto-Increment in MySQL doesn't meet my requirement so I'm thinking about making a new one. Here is my requirement: Create an increment serial num

Are the contents in a LMDB always stored BOTH in disk AND memory?

I'm wanting to use the rust implementation of LMDB but I can't seem to find whether it would always maintain a copy of whats in memory also in the disk and vice

How to write a query to find Median of column in a Table in MySql?

I was trying to solve problem in Hackerrank SQL Practice section and stuck in Problem 'Weather Observation Problem 20'. To find Median, I though of the followin

ERROR 1049 (42000): Unknown database 'tweetdata' Mysql

I have MySQL installed on an Ubuntu machine. When I run use TWEETDATA command it shows me following error ERROR 1049 (42000): Unknown database 'tweetdata' Bu

If "null=True", which is stored in DB "NULL" or "empty values"?

I created the django model "User" with "null=True" as shown below: # "myapp/models.py" from django.db import models class User(models.Model):

Is it possible to access an SQLite database from JavaScript?

I have a set of HTML files and a SQLite database, which I would like to access from the browser, using the file:// scheme. Is it possible to access the database

How to store tree structure in sql?

Here is my schema using sqlite, I am not sure if this is a good way to create tree structure in sql as I have to traverse many time to obtain the entire tree, a

How to find items in a collections which are not in another collection with MongoDB

I want to query my mongodb to perform a non-match between 2 collections. Here is my structure : CollectionA : _id, name, firstname, website_account_key, emai

Mongoose - remove multiple documents in one function call

In documentation there's deleteMany() method Character.deleteMany({ name: /Stark/, age: { $gte: 18 } }, function (err) {}); I want to remove multiple documents

UPDATE Query without WHERE Clause

Can the UPDATE query be used without a WHERE clause? And if so in what conditions?

Export data in parquet file in teradata

I cannot figure out a solution for exporting data from the Teradata database in a parquet format. I am using tdload and tbuild method which required tpt script

How to test an SQL Update statement before running it?

In some cases, running an UPDATE statement in production can save the day. However a borked update can be worse than the initial problem. Short of using a test

Find duplicate records in MongoDB

How would I find duplicate fields in a mongo collection. I'd like to check if any of the "name" fields are duplicates. { "name" : "ksqn291", "__v" : 0

how to pass a java object to oracle stored procedure with following details

I have my ORACLE table with structure as desc extraction_log1 Name Null

Drop default constraint on a column in TSQL

I have a table with a column like this that is currently live: name NVARCHAR(128) NOT NULL DEFAULT '' I am altering the column like this to make it nullable:

Make survey at laravel 5.4 and MySQL

I need to make a survey for my website. I have this: Route: Route::resource('survey','surveyController'); Controller: public function index() { $show=surve