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.
Learn more…3,414 questions
Sort by count of
-
3
votes1
answer4973
viewsWhat is the difference between the relationship with "identification" and the relationship with "non-identification"?(Mysql Workbench)
I have been learning Database for some time and do not know the difference. I would very much like to know. On the Internet I found answers, but they are not very enlightening.
-
3
votes1
answer218
viewsHibernate Criterias - Group Dates
Currently I can group dates using Projections.sqlGroupProjection(). When my date field is in the same class as I create the Criteria, it works perfectly. The problem is when I create an alias, and…
-
3
votes1
answer968
viewsHow to verify the occurrence of a string in a row and pick up x characters on the left and y on the right?
I’m having a problem with a Mysql query and I’m looking for help. Suppose I have many lines in the PROCESSES column and one of them is like this: IBAMAPROCUR: DF00025372 ADRIANA MAIA VENTURINIAPDO:…
-
3
votes1
answer3079
viewsGenerating HTML Page by PHP from the database
I am learning php with mysql and use wamp. I’m developing a site for academic-only terms, and I have a problem: I have a database with 20 pilots, and each pilot has information like age,…
-
3
votes1
answer86
viewsORACLE EXPLAIN PLAN, wrong values?
I’m using the explain plan of Oracle to raise some statistics and the following problem is happening: When I created the database, I created an X table with 50 Inserts. Soon after, I inserted about…
-
3
votes1
answer143
viewsAjax saving dynamically
I am trying to save the registration done, but when I open my modal, he does not understand that I am clicking on save and therefore he does not send the data, follow the code I am facing problems:…
-
3
votes1
answer464
viewsConfiguration of Postgresql
I am trying to access my Postgresql database, however I am getting the following error message: I have a virtual machine Debian 8 with postgresql 9.4 installed and I am trying to access via my…
-
3
votes1
answer225
viewsOdd characters
I have a database with that encoding: and I also have HTML with UTF-8 encoding. But for some reason the special characters appear this way: And I can’t figure out why it happens. Can anyone explain…
-
3
votes1
answer102
viewsI need to know how I use a . text as a database; I just need it to show the data contained in it
My application is a manual that when the user clicks on the item in the listview appears the descriptions contained in each item, along with a photo. Another thing like putting . text data in a…
-
3
votes2
answers56
viewsRemove messages from one caller without affecting the other
I am implementing a messaging system and need to make a way to remove messages from one caller without affecting the other. So-and-so and Sicrano exchange messages: At a certain point, Fulano…
-
3
votes1
answer2293
viewsHow do I add a new column between 2 columns in Postgresql?
How do I add a new column between two existing columns in my Postgresql database? In Mysql I use the function AFTER to add one column after another, and in Postgresql? How do I do this? SQL ALTER…
-
3
votes1
answer492
viewsSelect com Update
Would anyone know if there is an SQL calling to run a SELECT using LOCK IN SHARE MODE registry and running an UPDATE at the same time? example: SELECT * FROM Nome_Tabela WHERE id = 5 LOCK IN SHARE…
-
3
votes1
answer176
viewsComplex mapping Entity Framework
I am creating a class structure that follows the following form: Department -Service A department provides various types of service. A specific service can only be provided by one department, not by…
-
3
votes1
answer1008
viewsInstall database together with C#
I am finalizing an agenda of the meeting room that will be in the company reception, so I opted for the base to be locally and not networked. I intend to use Mysql or Sqlite. Is there any way I can…
-
3
votes2
answers7769
viewsLog table using Mysql
How to create a table of log Mysql audit that stores when and what was changed in each record? Mysql provides something that can facilitate this kind of thing?
-
3
votes3
answers100
viewsWill I lose my databases if I update SQL Server 2012 Express to Standard?
I have installed an instance 2012 Express, I need to update to the Standard, but to update I need to make sure that there will be no changes in the databases.
-
3
votes1
answer189
viewsIs there a simple method to test a logical data model?
It’s been a while since I learned the Entity-Relationship Model, and my teacher taught me that after the logical model is ready it’s always interesting to test the model to check for possible…
-
3
votes2
answers725
viewsHow can I save TXT file in C: directory using C#?
I’m trying to make a small data scrolling program and I want it to save a file. txt that stores the scrolls, so that it can be read later. The program is practically whole ready, all functionalities…
-
3
votes1
answer332
viewsFind the least-appearing numbers in the records
Personal greetings. I have a sort of table like this: reg num0 num1 num2 num3 num4 num4 1 4 2 5 8 10 15 2 3 7 8 15 20 21 3 14 10 6 21 17 1 4 1 4 8 10 16 7 5 9 3 2 1 8 15 I need to find out what the…
-
3
votes2
answers8499
viewsSubselect in Oracle bank
I am trying to elaborate a query and within one of my joins it is necessary to be made a subselect to ensure the integrity of the query as the example below: select t01.teste from teste t01 left…
-
3
votes1
answer2531
viewsOpen Database in format . DB
I have a database in a file .DB from an old application designed in Delphi. My client wants to migrate the data to use in a new application, however the old client software was designed in Delphi,…
-
3
votes3
answers1231
viewsHow does the Oracle Express Edition database work?
I would like an explanation as to the operation of the database Express Edition made available by Oracle for students, because by the terminal I created a table and made an insertion and everything…
-
3
votes1
answer2417
viewsHow to insert an encrypted field into a table in Postgresql?
I wanted to know how to insert an encrypted field into a table in the database. To illustrate my doubt let’s assume that I have the following java class: package pessoa; public class Pessoa {…
-
3
votes2
answers2742
viewsHow to backup the database to cloud and how to have the data synchronized across multiple devices?
Well folks my question is this. I have an App that has a local Sqlite database. I want to know if you have any library, framework, code that does the following: Backup that database to Cloud…
-
3
votes1
answer92
viewsSQL Server Rotary Records
I would like to know how to select records rotationally from a table. For example I have a table called disclosure and I want the records to be selected in such a way that today brings the element…
-
3
votes0
answers111
viewsMongodb stopping to work
We are in the company testing a project using Mongodb database. The database is installed on a Linux server (Centos), with 32GB of RAM, but sometimes the database para de funcionar and needs to be…
-
3
votes1
answer1190
viewsBest practices for storing images in Amazon S3 and saving in Mysql
I’m modeling a database, but I’m in doubt how to deal with this part of saving the image on Amazon S3 and easily referencing in the database. I intend to save the image URL (hosted on Amazon S3) in…
-
3
votes1
answer546
viewsWorking with high processing load in a table
What are the possible strategies of database modeling in a scenario where one has a specific table that receives a gigantic load of statements of insert, update and delete, in addition to high data…
-
3
votes1
answer698
viewsCan too high an ID (auto-increment) be harmful?
I have a table that has a very high turnover of information, that is, many records enter and many leave as well. With this the ID (auto-increment) is much higher than the value of data in the table.…
-
3
votes1
answer128
viewsMake query not showing some results
I have a table of CPF where the CPF’s registered. I need to make a SELECT where display all registered Cpfs, least 3 CPF’s. Something like: SELECT * FROM cpf WHERE cpf_id <>…
-
3
votes1
answer556
viewsFirebird C# standard Singleton
I am using the following function to connect to the database, I am programming in C# in Visual Studio 2013. namespace WindowsFormsApplication1 { static class Conexao { private static String strConn…
-
3
votes0
answers100
views -
3
votes2
answers3170
viewsIs it possible to store an Arraylist in a Java database?
In the case of Banco de Dados using Java, it is possible to store an object ArrayList in a Banco de Dados MySql? If yes, how can I store this type of data? And how can I recover it from the Data…
-
3
votes3
answers2223
viewsHow to group for weeks using sql?
I have the following problem . I have several requests , and I want to group them for weeks. I’ve seen several examples ,almost none helped me, I wonder if there is a function that when you put it…
-
3
votes1
answer1016
viewsError " Duplicate entry '1' for key 'PRIMARY' "
Good guys to with the following problem , when entering the data in a table I automatically insert the same data in the other two tables , but just right in the first row that I insert , when I…
-
3
votes1
answer2557
viewsRemove spaces via Update
I have a field called titulo, on the table noticias. Unfortunately, due to forgetting the command trim PHP, has several titles with space at the beginning and end of string. How can via SQL (Mysql)…
-
3
votes2
answers916
viewsSum of table fields with PHP and Codeigniter
I need to add some fields from a table. I have the transaction id and need to add all fields amount with id 224, all with 222.…
-
3
votes1
answer1299
viewsDate is not "blank" sql-srv
I have a column in the type database date. When I change some date in a form php and leave blank the same instead of being blank she brings me this date of 1900-01-01. Below the input I use to…
-
3
votes2
answers3629
viewsError trying to remove a temporary table
I have a service where I load data from an ERP into a DW. The source of the data is SQL Server 2008 R2 10.50.1600.1 and the target server MS SQL Server 2008 10.0.5512.0 SP3. The service performs a…
-
3
votes1
answer59
views -
3
votes2
answers1037
viewsHow to close connection to Firebird database
I am doing a project in Asp.net c# web Forms framework 4.5 and I did a test connection to a Firebird database, but when closing the connection it is not closing, I used the following code to open…
-
3
votes1
answer331
viewsSave Operations log to database with system user field
Hello, would like to know how to by means of triggers in the bank I get beyond saving the operations performed and in which table held also the user logged into the system (not the bank user, if the…
-
3
votes2
answers87
viewsDatabase objects as Stored Procedure parameters
Why when we pass database objects as parameters in a stored database they are not accepted? Ex: @COLUNA nvarchar(30), @VARIAVEL nvarchar(50) SELECT * FROM TBL_TESTE WHERE @COLUNA = @VARIAVEL The…
-
3
votes1
answer412
viewsGet all data from a table in a JSON - Indexeddb
Hello! I need to get all data from a table in a JSON. (Using the Indexeddb database). How to proceed?
-
3
votes0
answers92
viewsIntercept SQL s on a custom JDBC
You can create a custom implementation based on JDBC to intercept all sql s executed in the application? I did not find anything very concrete about this in Google, I made a simple test just…
-
3
votes1
answer227
viewsWhat does 'redacts password' mean?
In the Influxdb documentation, I found the following note: Note: Influxdb redacts passwords when you enable Authentication. Source:…
-
3
votes1
answer1598
viewsModeling for shared address table
I have 3 entities: Ponto, Solicitante and Serviço. Each one has its own address, but it is possible that the 3 have the same address. If an entity changes its address, it shall not change the…
-
3
votes2
answers1090
viewsShare cloud database (Postgresql)?
You can share a database (Postgresql) in the cloud, such as Dropbox, Google Drive? I want to share my database initially to access from different environments, just to start a new application. It is…
-
3
votes0
answers554
viewsHow to copy Firebird fdb database data to gdb
I have a database firebird in format fdb,on it has a table that I want to import to another bank firebird in format gbd. How do I do this process ?…
-
3
votes1
answer842
viewsBest way to structure history table with large amount of data
Functional requirement I own devices. Each device roughly has its unique identifier, an IP address, and a type. I have a routine of pings for every device that has an ip address. This routine is…