I'm learning SQL. I've heard that it's not possible to get user input in SQL? How are login and sign-ups made then? I'd really like to know if I just heard wrong or if you have to use another language or something like that to get input. Please explain? Thanks.
SQL is a language that is used to communicate with relational databases. You cannot write a program in SQL, so you will have to use some other language for that. To interact with a database, use the database API of that language, which will allow you to send SQL statements to the database.
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This is possibly a broad question:
I've been teaching myself how to program for the last year. I've learned how to create simple websites using HTML, CSS, and JavaScript. I've also learned how to create simple databases using PostgreSQL. I need help figuring out how to connect (API) the front end and the back end.
A friend suggested I learn how to use AWS RDS so I've already created a PostgreSQL DB instance there (tutorial). I've also connected to my DB using pgAdmin 4 using this tutorial.
What I would like to do is have my front end take in a number as the user's input and "submit" (POST) that value in the DB. Every time the user submits a new value, the new value is saved in the DB and the cumulative values of everything POSTed is returned to the front end for the user to see.
I know this project is a bit asinine but its a start. I can't find any more links on the internet to teach myself how to do this. If you have tips or resources (web links) to help me accomplish this, I would be really grateful.
Side note - I've also been studying python for the last year if that helps.
First, connect to the database like so:
$c1 = new PDO('pgsql:host=THERDSURL;user=THEDBUSERNAME;dbname=THEDATABASENAME;password=THEPASSWORD;connect_timeout=500',null,null);
Then start a new query like so:
$statement=$c1->prepare("select * from mytable");
Then execute it:
$statement->execute();
then loop through the results like so:
while($row=$statement->fetch());
{
var_dump($row)
}
it will vary a little depending on whether you're getting data or inserting data, but begin by learning how to get (select) data. Create a table using a GUI of some kind and learn how to query it programatically.
NOTE: Most people use a library of some kind to make the querying both more powerful and less complicated.. This code is in PHP, but a very similar process is done in many languages.
Note2: do not try to do any of this in javascript that's embedded in html or that's running on a client machine. Connecting to postgres using embeded javascript is not the normal way to go about doing this. Usually people use a language like PHP, Python, Java, etc.. and that's usually running on the server-- and although you can use javascript that runs on the server, I wanted to warn you about this because newer developers might not realize that javascript running on the server vs the browser has completely different capabilities where this is concerned.
is there a way to connect to a postgreSQL Database? I've noticed that the PHP module doesn't have the postgres extensions and its not possible to load it dynamically.
Is there any other way? An external PHP scripts will be the worst solution.
Alex
I don't have direct experience with Tide, but reviewing their docs here are the places I would look:
Javascript-> PostgreSQL Is there a possibility of connecting postgreSQL directly to Javascript?
Python -> PostgreSQL, like psychopg.
If that fails, along with other similar languages, MAY be able to find another driver written fully in a language like this.
The PostgreSQL protocol is extensively documented and several implementations exist for it. You could probably adapt either the Javascript driver or implement in another language to give you a direct driver to PostgreSQL http://www.postgresql.org/docs/9.1/static/protocol-flow.html
Im in the start up phase of creating an internal system based on PHP and MongoDB. The users of this system are Javascript programmers and would like to be able to make custom queries to the Mongo database from a frontend gui with arbitrary Mongo shell queries. Of course this would not be a problem at all if I forced them to to write the queries with proper PHP arrays etc, but i would definitely like to avoid this.
I am not quite sure how to approach a feature like this without writing some advanced methods being able to restructure the queries to proper formated arrays that can be used in MongoClient PHP. One approach would be making use of the i.e. MongoDB::execute() method and run the javascript on the database server - a method i don't fancy at all.
Im kindly asking if you have any ideas on how to achieve the requested functionalities to some extend.
Thank you in advance.
Are you looking for something like this : http://rockmongo.com/ ?
I have to create an Xpage web application which directly inputs data in a PostgreSql database. I've never worked with a PostgreSql database so I have absolutely no idea on how to approach this.
The application will be used through a browser if that matters.
Any help would be highly appreciated.
or, if you do not want to use the extLib for this purpose only, take a look at http://www.eknori.de/2011-07-03/using-mysql-data-in-xpages/ The article describes, how to access MySQL, but you can use the same code even for PstGreSQL with the correct JDBC drive.
The article also contains a link to OpenNTF where you can download the full source code.
You need to use a JDBC connection to connect to PostgreSQL. Use the extension library. This library contains a demo application which connects to a sql database using JDBC. Please take a look at this question : How do I access SQL from XPages.
I have a scenario where I need to send an email from my stored procedure in DB2.
However I have not been able to figure out any so far, apart from using Task Center or Query Patroller.
Can someone suggest me some pointers to this? I do not want to do it from any other language though. Thanks.
With 9.7, you can use the UTL_MAIL or UTL_SMTP built-in packages.
There is nothing built-in in DB2 to do that, like xp_sendmail in SQL Server.
You have to write your stored procedure in one of the hosted languages (Java, C++) and then use an API from that language to send the mail.
See this article on how to do it using Java.