data-modeling

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 9 days ago . Improve this question I have to present some complex queries and PL/SQL codes to people who don't know anything about my project. I need to explain how tables are connected, how conditions are affecting the outcome, joins, loops, etc. Is there a way to document this SQL and PL/SQL

问题 Given the schema below, how can a notification system be incorporated? Users need to be notified when someone comments on their Picture or SaleItem along with when someone makes a bid on their SaleItem (through Purchase Offer). The ultimate goal is to have a notification system that will handle SMS, Email, and an internal system messaging system. The complexities of those options will be worked out but I need the basic data model from which they can be built upon. MySql is the DB being used

问题 I kindly ask to point out the pros and cons of the solutions that I came up with for the challenge described below. Getting into the details of neo4j internals like how things are stored or processed is more than welcome. I would appreciate for referring to the points e.g. U.2 / A.1.A for clear distinction. I have been designing model where we have two types of actors: User and Administrator. User of the system can: U.1) list both valid OR invalid (issued OR revoked) Invitations with

问题 I have designed a database with some outside help and I am thinking about a major change to the database model because of a problem creating reports in Power BI I have recently encountered here: SQL Power BI Report with Bridge Table Disclaimer: if I could ask anyone within my firm, I would, but I can't. We have a three-layer structure A main table Firms , with information about the year and unique key/name for each firm A bridge table Firm_Bridge which information about the type of the firm

问题 I am running a dredge of a linear mixed effect model in the MuMin package in R, The model is quite big (see below) > Monster <- lmer(Fw.FratioFall ~ Average_mintemp_winter + (Average_mintemp_winter^2) > + percentage_woody_coverage + (percentage_woody_coverage^2) > + kmRoads.km2 + (kmRoads.km2^2) + Fracking > + WELLS_ACTIVED + (WELLS_ACTIVED^2) + BadlandsCoyote.1000_mi > + (BadlandsCoyote.1000_mi^2) + cougar_presence + COYOTE_springsurveys > + (COYOTE_springsurveys^2) + d3.1 + (d3.1^2) + WT

问题 For a business application, I am providing a base entity model. Thereafter the end user should be able to extend the model for his specific needs. For the base model I want to use database-first approach. But I don't know how to accommodate for allowing user to extend it. One part is to provide a UI for entity model editing and the other is to reflect the changes in the model and database thereafter. Please offer suggestions. EDIT : - Once the entity model is edited and saved, all EF

问题 For a business application, I am providing a base entity model. Thereafter the end user should be able to extend the model for his specific needs. For the base model I want to use database-first approach. But I don't know how to accommodate for allowing user to extend it. One part is to provide a UI for entity model editing and the other is to reflect the changes in the model and database thereafter. Please offer suggestions. EDIT : - Once the entity model is edited and saved, all EF

问题 I'm working on a personal project to learn about Redis. I'm trying to use it as the database for managing a hotel. I'm trying to wrap my head around how to manage reservations. The problem is, there are multiple rooms, and each room can have multiple reservations, storing date-from and date-to. I'm just unsure how i could model this, to efficiently be able to find an empty room for a given given period. Currently, I've been thinking of storing reservations, for each seperate room, in sorted

问题 I'm working on a personal project to learn about Redis. I'm trying to use it as the database for managing a hotel. I'm trying to wrap my head around how to manage reservations. The problem is, there are multiple rooms, and each room can have multiple reservations, storing date-from and date-to. I'm just unsure how i could model this, to efficiently be able to find an empty room for a given given period. Currently, I've been thinking of storing reservations, for each seperate room, in sorted

问题 I have financial data and my goal is to be able to forecast. I ran an arima model and found that the best fit was arima(1,1,1) w/ drift. I want to use GARCH on the data set because it is the better model to use due to volatility and when I squared my residuals it did have the arch effect. But I know that GARCH takes in a 2 parameter arima and I am not sure how that translates from the 3 parameter arima I currently have. library(dplyr) library(tidyr) library(lubridate) library(ggplot2) library