SQLite realizes user login function

SQLite realizes user login function void login::on_LoginToMain_clicked() { //The login button needs to determine whether the user name and password correspond correctly //If there is an error, a prompt dialog box will pop up //-------------------------------------- //Use SQlite to compare user name and password QSqlDa ...

Posted by ninevolt1 on Sun, 03 May 2020 21:36:07 -0700

SQL ite3 database C language simple operation basic data search (3)

SQL ite3 database C language simple operation basic data search (3) Overview: the creation, addition, deletion, and modification of sqlite3 database have all been mentioned. Today, it is the search of the database and the application of the core of database comparison. If the previous API is used for execution, because there is a return value ...

Posted by csj16 on Thu, 30 Apr 2020 00:17:15 -0700

[open source]. NETCORE. Netframework xamarin uses ORM FreeSql to access Sqlite

1. Create project We use the console type project to test the insertion, deletion, update, query and other functions, create a console project, and use the command: dotnet new console dotnet add package FreeSql.Provider.Sqlite dotnet add package FreeSql.Repository 2. Create a solid model using System; using FreeSql.DataAnnotations; pub ...

Posted by ubaldc36 on Sat, 18 Apr 2020 09:02:50 -0700

SQLite autoincrement

SQLite's AUTOINCREMENT is a key used to automatically increment field values in a table. We can use the autoconcent keyword on a specific list name to automatically increase the value of this field when creating a table. The keyword autoconcent can only be used for integer fields. grammar CREATE TABLE table_name( column1 INTEGER AUTOINCR ...

Posted by Hendricus on Sun, 12 Apr 2020 10:04:14 -0700

dotsql of Go Language Library Series

Guide: is it very interesting to be able to carry out a single line or lines of SQL files? Today, let's introduce this interesting Library -- dotsql. Background introduction dotsql is not an ORM or a builder of SQL query statements, but a tool that can carry out several lines in an SQL file, very similar to the reading of ini configuration fi ...

Posted by ~n[EO]n~ on Thu, 02 Apr 2020 19:14:54 -0700

Introduction to libdbclient interface

This is a magical development interface! It supports access to mysql, sqlite, Dream and oracle databases! It provides a unified C++ abstract interface externally, hides the internal implementation details, and has a learning cost of 0 for users! It provides abstract result table objects (result_ta ...

Posted by khovorka on Tue, 03 Mar 2020 19:51:13 -0800

Quickly read very large tables as data frames

I have a very large table (30 million rows), and I want to load it as a data frame in R. read.table() has many convenient functions, but it seems that there are many logic in the implementation that will slow things down. As far as I'm concerned, I'm assuming that I know the type of column in advance, that the table doesn't contain any column ...

Posted by Johnlbuk on Fri, 17 Jan 2020 07:09:11 -0800

iOS uses FMDB and FMDB migration manager to upgrade the database version

FMDB is generally used for data saving in iOS. Generally, fields will not be modified or added after being defined. If it is strict, we need to add the function of adding fields to the database. At present, FMDB and FMDB migration manager are used in the project to save the database version number and upgrade the database Acco ...

Posted by freddykhalid on Thu, 02 Jan 2020 13:50:06 -0800

Android Chapter 3 SQLite database

1. Use execSQL API to operate the database. Step 1: create the Class MyOpenHelper implementation interface SQLiteOpenHelper, copy the constructor, onCreate and onUpgrade methods; Step 2, after creating the myOpenHelper object myOpenHelper, use the relevant API of myOpenHelper to operate the database. package com.xiaohui.create ...

Posted by janey on Thu, 26 Dec 2019 13:24:13 -0800

java implementation of online editing and flow of word documents

Using pageoffice to realize document online editing and document flow 1: process Draft documents in the modified traceless mode, open them in the forced trace mode when leaders annotate their opinions, open them in the approval mode when the clerk cleans up the draft, and open the released official documents in the final read-only mode. Amon ...

Posted by Ferenc on Wed, 25 Dec 2019 12:10:17 -0800