Dynamically generate mysql query with php
I feel it’s too hard to write SQL queries to create that database. So if you want to generate MySQL queries based on form entries you might look into this functional generator below: Php Sql Query Builder https://github.com/nilportugues/php-sql-query-builder This allows you to take your form results and its field names(or ids) and code it into the Query Builder to generate your requested query!
Dynamically generate mysql query with php
I’m trying to learn how to dynamically generate a mySql Query based on the form fields that a user chooses to fill with data. In-order to make the learning process as easy as possible I’m using a simple form with a field for the users first name and last name. The basic (non-dynamic) version of the code is as follows:
What I need to be able to do is generate a query based on the data submitted. So if the user only enters their first name the query would read as :
$query = "SELECT * FROM members " . "WHERE first_name = '$first_name' "; But if the user enters both their first and last name the query would read as :
$query = "SELECT * FROM members " . "WHERE first_name = '$first_name' " . "AND last_name = '$last_name' "; Any help (or if someone can point me towards a good tutorial) would be greatly appreciated!
You can use PHP to check the input and append to the query when necessary.
$query = "SELECT * FROM members "; $query .= "WHERE first_name = '$first_name' "; if($last_name!="") $query .="AND last_name = '$last_name' "; Remember to escape the strings my using real_escape_string
$first_name = mysql_real_escape_string($_POST['first_name']); In case you want to check for the first name:
$query = "SELECT * FROM members "; if($first_name!="") < $query .= "WHERE first_name = '$first_name' "; if($last_name!="") $query .="AND last_name = '$last_name' "; >else
First, don’t use mysql_* functions in new code . They are no longer maintained and are officially deprecated. See the red box ? Learn about prepared statements instead, and use PDO, or MySQLi — this article will help you decide which. If you choose PDO, here is a good tutorial. (Credit)
Second, a caution to always escape user input being included in an SQL statement. Prepared statements handles this for you automatically.
Having said that, the PHP logic that you’re after is something like this:
real_escape_string($_POST['first_name']); $last_name = $mysqli->real_escape_string($_POST['last_name']); $sql = "SELECT * FROM members WHERE 1"; if (! empty($first_name)) < $sql .= " AND first_name = '$first_name'"; >if (! empty($last_name))
So if you want to generate MySQL queries based on form entries you might look into this functional generator below:
Php Sql Query Builder
This allows you to take your form results and its field names(or ids) and code it into the Query Builder to generate your requested query!
One bit of advice is to make sure that your field names match your table column names. This will make your process more seamless.
For example. In your case (assuming that your columns names match your form names and your table is named «members»):
select() ->setTable('members') ->setColumns(['first_name','last_name','email']); // write($query); ?> SELECT members.first_name, members.last_name, members.email FROM members Did are many complex queries that you can generate on the developer’s GitHub page.
Sql — How to generate data in MySQL?, There are two main approaches to generating data in MySQL. One is to generate the data on the fly when running the query and the other one is to have it in the database and using it when necessary. Of course, the second one would be faster than the first one if you’re going to run your query frequently. …
How to generate SQL queries
I am using phpMyAdmin to create database tables and fields. I have 100’s of tables in a single database. Now I need to make the same on few more servers.
I feel it’s too hard to write SQL queries to create that database. Is there any reverse process to generate an SQL query file from phpMyAdmin or anyother tool? I want to create a database in a GUI, and I need the SQL query for my database. Is there any tool to generate it automatically?
If I understood you correctly, you want to export a database (with many tables) using phpMyAdmin, and then import it and use it on another server.
Select the database on the left-hand side in phpMyAdmin and then: Export -> Select All Tables -> Adjust Options -> Go .
You are going to get .sql file, with all the table definitions inside. Then you can import it in another phpMyAdmin or other database handler.
You can use mysqldump to do this. Then —nodata switch should do what you want.
MySQL PHP Generator, To use a SELECT query as a page data source, click the Create Query button or select the corresponding popup menu item, specify the query name and text, and click OK. Rules for creating queries used by PHP Generator. All queries must satisfy the simple requirement: the following query must be correct. select * …
How to Intentionally Create a Long-Running MySQL Query
I know this is an odd question to ask, but I’d like to find out if there is a MySQL query I can create without already having millions of rows in my database that will consume resources and run for a long time. My ultimate goal is to test my application in cases of resource contention and make sure that my methods for handling failure (specifically server timeout) are correct.
If there another way I can test this without creating and executing a high-resource query, I’d appreciate hearing that as well.
I assume you could use benchmark() for this, although that isn’t the scope of it.
select benchmark(9999999999, md5('when will it end?')); If you need them to run for a bit, but not that long, then try
select benchmark(1000000, md5('when will it end?')); -- around 0.3s select benchmark(10000000, md5('when will it end?')); -- around 3s select benchmark(100000000, md5('when will it end?')); -- around 30s For those wondering how to achieve a similar operation for MS SQL Server (not MySQL), use WAITFOR DELAY ’02:00′ if you want to test timeouts.
Generate GUID in MySQL for existing Data?, UPDATE Another solution that doesn’t use triggers, but requires primary key or unique index : UPDATE YourTable, INNER JOIN (SELECT unique_col, UUID () as new_id FROM YourTable) new_data ON (new_data.unique_col = YourTable.unique_col) SET guid_column = new_data.new_id.
PHP QR Code Generator with SQL statement
I would like to use the results of a MYSQL query and generate a batch of QR Codes have the following php script via PhpQrCode. What I need is simply display the list of barcodes generated on HTML page. This is what I wrote so far:
"; echo "
"; > ?> The query is correct since I tested it out but I only get a blank page with a sort of broken image. Can someone help me as to what I am doing wrong please?
To render the image in the html page, hold the returned QRcode image in a location and then specify it as a link in src attribute of tag.
If QRcode::png returns the raw image data, use data URIs to display:
$qr_code = base64_encode(QRcode::png ($row['Description'])); $src = 'data: image/png;base64,'.$qr_code; echo ''; I have stored the PNGs as files via variable $filename.
Php — How to generate unique id in MySQL?, You may like the way that we do it. I wanted a reversible unique code that looked «random» -a fairly common problem. We take an input number such as 1,942. Left pad it into a string: «0000001942». Put the last two digits onto the front: «4200000019». Convert that into a number: 4,200,000,019.