Questions tagged as 'mysql'

Tagged questions
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Sort Varchar field taking into account groups and subgroups

I need to sort the values below in ascending order. They are of type Varchar and the solutions I have found so far for MySQL did not work. An example of the data type would be 1.12.02 , as these values serve as specific code for a chart...
asked by 26.09.2016 / 19:38
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Is it really necessary to create a 3rd auxiliary table in N-N relationships?

In several places I see that when you have a N - N relationship (if memory does not crash) it is recommended to create a 3rd helper table and then later it will be transformed into a 1 - 1 relationship ( also if memory does not fai...
asked by 17.07.2017 / 16:44
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Query on two tables without INNER JOIN

I wonder, is there a difference in the performance of these two queries? in MySql SELECT employee.*, company.name FROM company, employee WHERE employee.company_id = company.id AND company.id = '365' or SELECT employee.*, company.name F...
asked by 26.03.2014 / 19:43
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What are the appropriate data types for columns like address, email, phone, and mobile for SQL database?

What kind of data is recommended to create the following fields: address, email, cell / phone number?     
asked by 04.02.2014 / 20:13
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What is the difference between the LOCATE and INSTR functions?

The description of the function LOCATE , in free translation, is: Returns the position of the first occurrence of substring. The description of the function INSTR , in free translation, is: Returns the index of the first occurrenc...
asked by 18.05.2017 / 20:29
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MySQL = MariaDB?

For some days I've been teaching the teacher saying:    Oracle bought MySQL and just renamed it to MariaDB . As I am not easy to believe in the things spoken, I went to research on the subject and for the little that I read,...
asked by 21.02.2018 / 13:28
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Close connection to database C #

I am making a login system and I get the exception sql message when I try to create a new account in the database: MySqlCommand usuaExiste = new MySqlCommand( "SELECT * FROM contas WHERE nome = '"+textBox1.Text+"'", bdConn); bool resultado...
asked by 21.02.2014 / 20:45
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How do I SELECT on 2 or more Tables with 2 or more conditions?

I have a problem making a select with the following conditions: I want to display the data with either condition1 or condition2 Select * tabela inner join tabela2 WHERE campo = 0 and campo2 = '' and campo3 or campo10 is NULL Select all the...
asked by 11.03.2014 / 11:14
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SQL command to display specific records of the "id" field

What SQL statement would display the records where the id field was 22, 23, 25 and 27?     
asked by 30.08.2014 / 02:21
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How to display the result of a query in a html page in PHP?

How can I display the results of a query in a one-page html table? Below is what I was able to do. However, the code only shows the first record. include("conectar.php"); $sql = mysql_query("Select * From tb_trabalhador and tb_detalhe_traba...
asked by 31.01.2014 / 17:53