Questions tagged as 'mysql'

Tagged questions
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questions about category and subcategory

Good afternoon I created a system of category of products in the store that I am putting in it I have a page that calls for get the categories but I have a problem I have more than one category per product and I am not able to do list it so much...
asked by 31.08.2015 / 21:25
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Do SQL query in 3 tables and return the value to another table? [closed]

I have 3 tables (A, B, C) with column descricao (with different records between them). I want to make SELECT of the three tables and send the result to another table D. It would be something like this: SELECT A.descricao, B...
asked by 02.10.2015 / 17:45
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I want the result of a query and in SQL it is simple ... in PHP it is confusing

I just want the result of a SELECT in php and I do not know how to get the result: $descricao = mysqli_query($this->conexao, "Select descricao from tabela where codigo = 1"); var_dump ("$descricao"); Return a array and ho...
asked by 27.05.2018 / 22:02
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Creation of an Identification Code with PHP and MySQL [closed]

I'm starting to work with programming now and I have a lot of doubts. I need to create a specific "TAG" for equipment registration. This TAG must have 4 letters + 4 digits, eg: CEME-0001. The first four letters refer to the sector that the equip...
asked by 26.05.2018 / 19:58
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COM serial port

I'm trying to run a code every time, where it takes the value sent by the Arduino COM port, prints it in a textbox, and then generates an insert in the mysql database. It just read what was sent by the COM port and does not execute the insert...
asked by 03.04.2017 / 15:26
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Arithmetic operations in Java with data from the database [closed]

What is the best way to calculate values in java? I need to make a method that returns the sum of all input and output and subtraction. Example: Insert all entries in Double in column X, and all double output in column Y (get the total of each c...
asked by 25.05.2017 / 22:09
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Join 2 SQL with different results [closed]

asked by 27.01.2017 / 16:43
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Indicate a column if it exists in ALL elements of another SQL

I have the following question: "Enter the" name3 "which are in ALL" name ". And I have 4 tables that are below -- A (name,Num2, local) insert into A values ('Favela',1,'WE'); insert into A values ('Lamosa',2,'NA'); insert into A values ('Lu...
asked by 01.12.2016 / 12:41
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Search by date not working

I am trying to search mySql database by filtering by date and it is not bringing any results. In the screen below I was able to search for the other criteria Thisisthecodethatisdoingthesearches.publicvoidmontaTabelaBusca(){Stringcriterio=" W...
asked by 16.04.2017 / 21:22
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Assign value in SQL variable

How do I make a select that assigns the value "10" in all of the games column? NOTE: Do not give update in the table. /*minha_tabela*/ codigo jogos --------------------- 1 10 2 10 3 10...
asked by 15.04.2017 / 04:18