Most voted "database" questions
A database (its abbreviation is BD, DB, database) is an organized collection of data typically used to model certain situations. Use this tag if you have questions about designing a database. If this is a specific database management system, like Mysql, for example, use this tag instead.
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answer766
viewsRelational library model, huh?
This model I made this cool or is redundant yet? [Edited] The database has been modified. Can I now have better queries? Here’s how it is now:…
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answer27
viewsNo PHP connection response
Good evening, could someone help me? I’m doing an academic project where I have to link HTML pages and make them pull information from the database. So far, I have created a table in my database,…
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answer785
viewsConnect Database with HTML
How do I connect my database to html? HTML CODE <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> <title>CADASTRO DE CLIENTES COM BANCO…
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answer38
viewsI can’t get the date on the chart
I’m doing the following command: SELECT h.h_dia FROM hh h WHERE h.h_dia = 20180621 GROUP BY h.h_dia
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answer65
viewsDatabase query with java
I will make a comparison with my problem using a database functionality and html Jquery. With Jquery we have the possibility to visit the database and bring the data to the frontend in HTML, and…
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answer237
viewsI cannot connect the Mysql Nodejs database
It should show the table data on the screen, but does not return anything. Where I am missing? module.exports = function(app){ app.get('/noticias', function(req, res){ var mysql = require('mysql');…
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answers250
viewsMysql - INNER JOIN - INDEX
Guys, I got one query here very simple with JOIN, Because banks have a lot of records, I need to index... But I’m getting it for kct... What is the best way to index in a JOIN? (That one query takes…
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answer36
viewsConnection 4 to mongodb.net:27017 closed
I’m learning to work on Mongodb and out of nowhere, this "mistake" starts to appear. Does anyone know how to fix it? Programming language I’m using: Java
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answers30
viewsImages in the Mysql BD in the java language
Iqeria know how to insert images into the database so that when I can search the image and its data appear.
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answer94
viewsI’m having trouble saving input data to a mysql table via PHP
I’m trying to understand why I’m making a mistake at the moment I will save the entered data to us input in a mysql table via PHP? does anyone know how to solve? <?php require_once…
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answer74
viewsDoes connecting to a java database have to be by a main class only?
To make a connection to the java database, I only have to do it through a main class or I can do it through another class?? public class ConexaoBasica { public static void main(String[] args) throws…
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answers65
viewsWhat term use 'date' or 'create_at'?
Contextualizing: I have the following table and store the creation date in the attribute date. +------------+ | Operation | +------------+ | id | | amount | | type | | date | | product_id |…
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answer1008
viewsVIEW DATE BY PHP SPELL
Guys, next.. I have a contract printing page where I need to convert the field date in full <?php echo $result->estado?> - <?php echo $result->data_contrato?> In the…
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answer73
viewsData does not save in Firebase
I’m trying to save data in my Firebase database but the app doesn’t save. I can install, boot the app, and move between pages without an app crash, but I can’t save data. Before implementing the…
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answer113
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answer60
viewsHow to make condition with msql number
Personal need a lot of help I have an input for the person to make a money transfer but if that person has 30 real money and she type a value of 100 real to make the transfer she will be with…
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answer82
viewsDoubt about changing data in PHP MVC
I need to update a client’s data on my MVC project. It is a form that must update two tables in the database: "user" and "patio", but only "user" is being updated, which can be? Returns no error,…
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answers78
viewsQuestions about database modeling, ID duality
I am creating a system aimed at law firm, and in the middle of the development emerged the following situation: There are the following tables (summarized): TB_PROCESSO possessing: IDPROCESSO…
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answer42
viewsHow to copy data from one column to another column of the same table
Hello, good afternoon. I have a column table called City where inside it has 5 fields(Codecompleto(PK), Code, Name, State, Nameclear). This Nameclear was created to receive the Name without accents.…
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answer111
viewsCreate mysql table
I need to create, in the database, the table below, and insert the values shown. My question is **what would be the primary key in this table ? **ID_NF ? In exercise asks to only create this table,…
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answer57
viewswhere do I use left Join in this case? no msql
I need to put the left join in which case here you can tell me where the mistake is? select a.nome_artista, count(*) as numero_musicas from artista a, musica m where m.id_artista = a.id_artista…
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answer24
viewsSQL Server How to link the name of a column to an external variable?
Good morning Srs I made an SQL code that separates an item from each record from a column without repeating, and is working correctly, follows code below: SELECT Tab_Dados_Escolha.Nome_Produto FROM…
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answer155
viewsWhy is my foreach duplicating my database records?
function DBRead($table, $params = null, $fields = '*'){ $table = DB_PREFIX.'_'.$table; $params = ($params) ? " {$params}" : null; $query = "SELECT {$fields} FROM {$table}{$params}"; $result =…
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answers33
viewsLaravel : Form and fetch the ID
Is there any way to fetch the ID (to store in the BD) and the name for the user to select ? <option selected>Escolher Capitulo</option> @foreach($capitulos as $cap) <option…
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answer1151
viewsColumn id with Primary key and auto increment is returning null MYSQL PHP
Good evening guys, it is the following, I have an application that was working until these days, then today when I went to add a post in the database, my id_post that is Primary Key and…
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answer65
views0097 - missing parentheses on the right. - Can help
I know you already have some negotiations here in the forum about this error 0097 - missing parentheses to the right.. This is my command, you can help me ? select distinct Coalesce(Sum(Case When…
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answer28
viewsSelect from SQL tables
Good morning, everyone! I’m performing the select below: select * from orcamento where status_orcamento = 'A' and data_conclusao_orcamento > 2021-05-31 My question is: Information should only…
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answer14
viewsCan an Enum table in the database store more than one value for the same element?
public enum SitucaoEnum { INCLUSAO(1), CANCELAMENTO(2), ATUALIZACAO(3), FINALIZACAO(4); } Can I save more than one such value in a type Enum column in the database? Or only rescue of one Enum per…
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answers25
viewsUPDATE table 1 with data from table 2
Good morning, I’m having some difficulties to take dice from one table and play to another. I already tried INNER JOIN and could not. I have that data: Table 1 = nft | Column = walletAdress Table 2…
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answers20
viewsIn which bank should I save logs?
I want to save logs of my applications in a database, Mysql or Mongodb. However as it will be a large volume of logs, I will save in a different database from the application. I am in doubt of which…
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answer1071
viewsAdvantages and disadvantages of Sqlite
Sqlite is a powerful API for working with structured data, but it requires a lot of effort from the programmer to use it. According to Developer (2018), the programmer faces the famous "Boilerplate…
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answer16
viewsUpdate records by blocks
Hi, I need to make a update in a field (called block) for each given amount of records. I have 100 records, for every 10, I must enter a (automatic) number in the field. The idea is to divide the…
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answer31
viewsI can’t enter data into the database
The page loads all right , however the columns are empty in the bank { <?php $servername = "localhost"; $database = "login"; $username = "root"; $passwd = "odair"; $conn =…
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answer2475
viewsWhere is the data stored in Mysql 8?
Two days ago I started studying about the Mysql and so far I only know his basics, not to mention that he’s the first SBGD what study. One very interesting thing about Mysql that I found, is that…
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answer61
viewsUse of jquery to pull records, but does not appear
I saw in a celke tutorial, select the BD using php and list the records using jquery. I can see you pulled the data, but when it comes to showing inside the span, it doesn’t. I wonder where I went…
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answer606
viewsLaravel Database name error seems incorrect how to resolve?
I recently created a Previder service, which kind of works. however when I will capture the database data using Produtos::all(); I get the following error: Database name seems incorrect You’re using…
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answer28
viewsHow to identify weekly clients that appear in one table and not another in sql?
Hey, all right, guys? Well, I need to identify weekly clients who have an active plan but didn’t use the plan that week. I have two tables, one that contains the type of client’s plan and another…
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answer1670
viewsINSERT conflicted with FOREIGN KEY constraint
I have a problem when performing INSERT in a table in my BD because whenever I try to perform INSERT SQL Server return me this : The INSERT statement conflicted with the FOREIGN KEY constraint…
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answer49
viewsregistration form ,does not present error,and goes to index/ But does not register
FORM/INSIDE A PAGE <!-- Page Content ================================================== --> <div class="container"> <div class="row"> <div class="col-xl-5 offset-xl-3">…
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answer45
viewsError connecting to Debian localhost database
I created a virtual machine and installed Debian. After I installed the Cassandra and checked the status to know that the bank is running. but when executing the command cqlsh in localhost I get the…
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answer426
viewsUnknown column '' in 'Where clause'. Error mysql php
Below is the code I am using to try to make a login system, but it is failing Code: <?php $link = mysqli_query($con, "SELECT * FROM usuarios WHERE nome= $nome AND senha = $senha") or…
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answer133
viewsjava.lang.Nosuchmethooverthrow: No virtual method group(Ljava/lang/String;)Ljava/lang/String;
Oie I have a problem with an app in Android Studio, it compiles and runs on my phone, but when I click on some button it gives this error. Error: E/AndroidRuntime: FATAL EXCEPTION: main Process:…
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answer40
viewsI cannot understand/find the error in php code
I am creating a client registration system and when I run . php it simply appears this error: php code: <?php $login = $_POST['inputEmail']; $senha = MD5($_POST['inputSenha']); $connect =…
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answer192
viewsconvert BLOB image value to.jpg image again
I need to make the code below not show the blob value of the image q was saved in the database, but show it in figure.jpg to list on the screen. how can I convert inside that same code? <?php…
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answer32
viewsHow to register the value of an input="text" in the database?
How can I include the value of the name input identificador to be saved in the database, with the code below: <?php require_once "conexao.class.php"; $conexao = new…
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answer147
viewsHow to create a function to delete all database records with Postgresql?
I need to create a script to delete all records from my database in all tables, without deleting the tables and restarting the sequence. I know I should use the TRUNCATE or the DELETE. My bank has…
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answers88
viewsDjango/Python primary key generator with low collision risk and good performance
GENERATING UNIQUE PRIMARY APPLICATION KEYS I would like to get tips on how to generate primary keys with low risk of collision and that do not reduce the performance of Postgresql operations.…
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answer27
viewsWrite many inputs to bd
<form method="POST" action="proc_editar_despacho.php"> <div class="form-group"> <div class="card"> <div class="card-body"> <label…
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answer25
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viewsjsonb_array_length() in subquery with Insert
I have this query where I try to do an Insert through the main query, but I believe that on account of json_array_legth() it does not let me insert presenting the following error: SQL Error [22023]:…