All Questions

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Calculate result with previous record and update in the new record

I want to take a tour of the 'data' table and in each of the registers I need to take the Mileage from the previous record, then subtract New Mileage - Old Mileage and divide it between Liters to get Efficiency and assign it to the record, but I...
asked on 22.09.2018 / 00:42
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Why does the same date appear on all Users?

I am in Java, and I want to show the users that I have in the database, I make the query and it collects it well, I insert them well in an ArrayList and when I show it, only the date of birth of the last user appears. Why? try { senten...
asked on 12.11.2018 / 13:35
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Help with python functions

I made a code that uses some functions. Such functions give a value to n and as they are called, the value of n changes (these functions are at the beginning of the code). What happens is that when you execute the script, so do not call the func...
asked on 06.11.2018 / 03:37
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How to play an mp3 every x minutes when entering a page

I'm making a player where several music sounds and I want every x minutes, apart from the player, to play a single music without touching any button, only when entering the page, and in those x minutes the music sounds , right now...
asked on 09.11.2018 / 14:18
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How can I remove a field from a multidimensional array?

You see I have a multidimensional array and I need to remove a field from that array but I can not get it. I must clarify that I am using firestore firestore. That's my code: db.collection("database").doc("users").get().then(data => {...
asked on 01.11.2018 / 07:39
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SQL query Advanced filter with Postgres

I have this database model I want to make a query that meets the following conditions. all students must be listed I want to be able to see the type of characterization only of the characterization with the highest order semester...
asked on 20.11.2018 / 05:31
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Insert and Search in Datetime field

I'm trying to insert a date with milliseconds, but I can not do it. The bash date has the following format: "%d%m%Y%H%M%S%2N" While in BBDD I see the following: MariaDB [db]> INSERT INTO access_wifi(DATA) VALUES ('0511201813450367'); Q...
asked on 05.11.2018 / 14:47
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how to know how many records a query returns sql server 2012 with php

I have the following query SELECT * FROM REPORTE and I want to know how I do to count how many records are in the table, in SQL Server 2012. With php I can not find how to perform certain functions based on the number of records.     
asked on 22.08.2018 / 22:48
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Count records of three SQL server tables

I have the following: Tabla1: "CAT_SEXO" Campos: SEXO_ID/SEXO Tabla2: "CONDUCTORES" Campos: sexo_id Tabla3: "LICENCIAS" Campos: fecha_captura for mentioning the data of interest for my question. The point is that I need to consult the n...
asked on 22.08.2018 / 23:25
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How to generate output with colors from shell script bash to file and maintain the colors?

I'm developing a utility in a bash shell script (file.sh), I can generate colors when the output goes to console, for example with a code like: echo -e "\e[1;33m Aqui el mensaje \e[0m"; But my idea is to create a log file as identical as po...
asked on 29.10.2018 / 17:27