Elvis Miranda

Elvis Miranda

1560917038

How to Using Multiple Database in Nodejs

Unfortunately, the Sequelize documentation did not cover this specific topic and multiple stackoverflow posts had to save the day. To save you time, I decided to write a post, summarizing my approach and some helpful tips and tricks.

The Sequelize documentation states:

Sequelize will setup a connection pool on initialization so you should ideally only ever create one instance per database if you’re connecting to the DB from a single process.

This means, that we will need to run a new Sequelize instance for every database we want to connect to our server. The easiest and most flexible way to do this is to declare multiple databases in our config.js and then loop over these databases in the file handling our database connections (in my case this is the index.js of my models folder).

module.exports = {
  
  /**Declaration of databases for my development environment**/
    "development": {
        "databases": {
            "Database1": {
                "database": process.env.RDS_DATABASE1, //you should always save these values in environment variables
                "username": process.env.RDS_USERNAME1,  //only for testing purposes you can also define the values here
                "password":  process.env.RDS_PASSWORD1,
                "host": process.env.RDS_HOSTNAME1,
                "port": process.env.RDS_PORT1,
                "dialect": "postgres"  //here you need to define the dialect of your databse, in my case it is Postgres
            },
            "Database2": {
                "database": process.env.RDS_DATABASE2, 
                "username": process.env.RDS_USERNAME2,  
                "password":  process.env.RDS_PASSWORD2,
                "host": process.env.RDS_HOSTNAME2,
                "port": process.env.RDS_PORT2,
                "dialect": "mssql"  //second database can have a different dialect
            },
        },
    }
}

config.js

Here we declared two databases — The Postgres Database “Database1” and the MSSQL Database “Database2” — and their credentials for the connection. Now let’s have a look how to read in these declarations and connect to the databases.

const Sequelize = require('sequelize');
const env = process.env.NODE_ENV || 'development';

//Load the configuration from the config.js
const config = require(`${__dirname}/../config/config.js`)[env];

//Create an empty object which can store our databases
const db = {};

//Extract the database information into an array
const databases = Object.keys(config.databases);

//Loop over the array and create a new Sequelize instance for every database from config.js
for(let i = 0; i < databases.length; ++i) {
    let database = databases[i];
    let dbPath = config.databases[database];
    //Store the database connection in our db object
    db[database] = new Sequelize( dbPath.database, dbPath.username, dbPath.password, dbPath );
}

/**Load Sequelize Models**/

index.js

The “db” object now contains information on how to connect to all databases configured in our config.js, but does not contain information about the models in the database, consequently not being able to make correct SQL queries. To give the “db” object the necessary model information, we need to read the information from our model files and add it to the object. To understand the next few lines of code, we first need to have a look at my folder structure. The index.js is located in the models folder, which has two subdirectories for models of both databases from my config.js:

Now lets add the models from both directories to our “db” object in the index.js:

const fs = require('fs');
const path = require('path');
const Sequelize = require('sequelize');
const basename = path.basename(module.filename);
const env = process.env.NODE_ENV || 'development';
const config = require(`${__dirname}/../config/config.js`)[env];
const db = {};
const databases = Object.keys(config.databases);

/** Add Databases**/
for(let i = 0; i < databases.length; ++i) {
    let database = databases[i];
    let dbPath = config.databases[database];
    db[database] = new Sequelize( dbPath.database, dbPath.username, dbPath.password, dbPath );
}

/**Add the Database Models**/
//Add models from database1 folder
fs
    .readdirSync(__dirname + '/database1')
    .filter(file =>
        (file.indexOf('.') !== 0) &&
        (file !== basename) &&
        (file.slice(-3) === '.js'))
    .forEach(file => {
        const model = db.ebdb.import(path.join(__dirname + '/database1', file));
        db[model.name] = model;
    });


// Add models from database2 folder

fs
    .readdirSync(__dirname + '/database2')
    .filter(file =>
        (file.indexOf('.') !== 0) &&
        (file !== basename) &&
        (file.slice(-3) === '.js'))
    .forEach(file => {
        const model = db.easyconnect.import(path.join(__dirname + '/database2', file));
        db[model.name] = model;
    });

Object.keys(db).forEach(modelName => {
    if (db[modelName].associate) {
        db[modelName].associate(db);
    }
});


module.exports = db;

index.js

Now we can require our models in our controllers as usual:

const model1= require('../models').model1;

Congratulations! You added multiple databases to your NodeJS server and made them accessible. Now let’s talk about the tricky part: migrations and seeders

Sequelize is currently not supporting multiple migration folders and is not able to distinguish, which migrations should be ran in each database by itself, if all migration files are kept in one folder. While there are multiple ways to deal with this problem — e.g. manually setting migration filepaths in the sequelize cli — I found the approach using separate options files and npm scripts the most productive:

First lets expand our config.js with environments for migrating and seeding our databases. Every environment then only contains data for one specific database, so we can explicitly define to which database we want to connect:

module.exports = {
    "development": {
        "databases": { /** our database declarations from before**/}
    },

    // Special environment only for Database1
    "Database1": {
                "database": process.env.RDS_DATABASE1, //you should always save these values in environment variables
                "username": process.env.RDS_USERNAME1,  //only for testing purposes you can also define the values here
                "password":  process.env.RDS_PASSWORD1,
                "host": process.env.RDS_HOSTNAME1,
                "port": process.env.RDS_PORT1,
                "dialect": "postgres"  //here you need to define the dialect of your databse, in my case it is Postgres
            },

    // Special environment only for Database2
    "Database2": {
                "database": process.env.RDS_DATABASE2, 
                "username": process.env.RDS_USERNAME2,  
                "password":  process.env.RDS_PASSWORD2,
                "host": process.env.RDS_HOSTNAME2,
                "port": process.env.RDS_PORT2,
                "dialect": "mssql"  //second database can have a different dialect
            },

config.js

In the next steps we create new Sequelize options files — similar to our .sequelizerc file — for every database. So lets create these two files in the directory of our package.json file:

  • .sequelize-database1
  • .sequelize-database2

In these files, we can define in which directory our config, models, migrations and seeders are stored:

const path = require('path');

module.exports = {
    "config": path.resolve('./server/config', 'config.js'),
    "models-path": path.resolve('./server/models'),
    "seeders-path": path.resolve('./server/seeders/database1'),
    "migrations-path": path.resolve('./server/migrations/database1')
 };

.sequelize-database1

const path = require('path');

module.exports = {
    "config": path.resolve('./server/config', 'config.js'),
    "models-path": path.resolve('./server/models'),
    "seeders-path": path.resolve('./server/seeders/database2'),
    "migrations-path": path.resolve('./server/migrations/database2')
 };

.sequelize-database2

Finally we can use these options files in npm scripts, that run our migrations oder seeders. Therefore we need to add some lines to the scripts section of package.json file:

{  

  "scripts": {

      "sequelize:database1:migrate": "sequelize --options-path ./.sequelize-database1 --env database1 db:migrate",
      "sequelize:database1:migrate:undo": "sequelize --options-path ./.sequelize-database1 --env database1 db:migrate:undo",
      "sequelize:database1:seed:all": "sequelize --options-path ./.sequelize-database1 --env database1 db:seed:all",

      "sequelize:database2:migrate": "sequelize --options-path ./.sequelize-database2 --env database2 db:migrate",
      "sequelize:database2:migrate:undo": "sequelize --options-path ./.sequelize-database2 --env database2 db:migrate:undo",
      "sequelize:database2:seed:all": "sequelize --options-path ./.sequelize-database2 --env database2 db:seed:all",
    },
}

package.json

The scripts use the two .sequelize-database1, .sequelize-database2 options files to determine the location of the configuration, models, migrations and seeder directories and set the correct environment for reading configurations from the config.js file.

You can run the scripts with an npm run command from the command line:

npm run sequelize:database1:migrate

I hope this article could help you setting up multiple database connections to a single NodeJS server with Sequelize. If you have any questions, feel free to ask them in the comment section.

#node-js #javascript 

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How to Using Multiple Database in Nodejs
Chloe Butler

Chloe Butler

1667425440

Pdf2gerb: Perl Script Converts PDF Files to Gerber format

pdf2gerb

Perl script converts PDF files to Gerber format

Pdf2Gerb generates Gerber 274X photoplotting and Excellon drill files from PDFs of a PCB. Up to three PDFs are used: the top copper layer, the bottom copper layer (for 2-sided PCBs), and an optional silk screen layer. The PDFs can be created directly from any PDF drawing software, or a PDF print driver can be used to capture the Print output if the drawing software does not directly support output to PDF.

The general workflow is as follows:

  1. Design the PCB using your favorite CAD or drawing software.
  2. Print the top and bottom copper and top silk screen layers to a PDF file.
  3. Run Pdf2Gerb on the PDFs to create Gerber and Excellon files.
  4. Use a Gerber viewer to double-check the output against the original PCB design.
  5. Make adjustments as needed.
  6. Submit the files to a PCB manufacturer.

Please note that Pdf2Gerb does NOT perform DRC (Design Rule Checks), as these will vary according to individual PCB manufacturer conventions and capabilities. Also note that Pdf2Gerb is not perfect, so the output files must always be checked before submitting them. As of version 1.6, Pdf2Gerb supports most PCB elements, such as round and square pads, round holes, traces, SMD pads, ground planes, no-fill areas, and panelization. However, because it interprets the graphical output of a Print function, there are limitations in what it can recognize (or there may be bugs).

See docs/Pdf2Gerb.pdf for install/setup, config, usage, and other info.

pdf2gerb_cfg.pm

#Pdf2Gerb config settings:
#Put this file in same folder/directory as pdf2gerb.pl itself (global settings),
#or copy to another folder/directory with PDFs if you want PCB-specific settings.
#There is only one user of this file, so we don't need a custom package or namespace.
#NOTE: all constants defined in here will be added to main namespace.
#package pdf2gerb_cfg;

use strict; #trap undef vars (easier debug)
use warnings; #other useful info (easier debug)


##############################################################################################
#configurable settings:
#change values here instead of in main pfg2gerb.pl file

use constant WANT_COLORS => ($^O !~ m/Win/); #ANSI colors no worky on Windows? this must be set < first DebugPrint() call

#just a little warning; set realistic expectations:
#DebugPrint("${\(CYAN)}Pdf2Gerb.pl ${\(VERSION)}, $^O O/S\n${\(YELLOW)}${\(BOLD)}${\(ITALIC)}This is EXPERIMENTAL software.  \nGerber files MAY CONTAIN ERRORS.  Please CHECK them before fabrication!${\(RESET)}", 0); #if WANT_DEBUG

use constant METRIC => FALSE; #set to TRUE for metric units (only affect final numbers in output files, not internal arithmetic)
use constant APERTURE_LIMIT => 0; #34; #max #apertures to use; generate warnings if too many apertures are used (0 to not check)
use constant DRILL_FMT => '2.4'; #'2.3'; #'2.4' is the default for PCB fab; change to '2.3' for CNC

use constant WANT_DEBUG => 0; #10; #level of debug wanted; higher == more, lower == less, 0 == none
use constant GERBER_DEBUG => 0; #level of debug to include in Gerber file; DON'T USE FOR FABRICATION
use constant WANT_STREAMS => FALSE; #TRUE; #save decompressed streams to files (for debug)
use constant WANT_ALLINPUT => FALSE; #TRUE; #save entire input stream (for debug ONLY)

#DebugPrint(sprintf("${\(CYAN)}DEBUG: stdout %d, gerber %d, want streams? %d, all input? %d, O/S: $^O, Perl: $]${\(RESET)}\n", WANT_DEBUG, GERBER_DEBUG, WANT_STREAMS, WANT_ALLINPUT), 1);
#DebugPrint(sprintf("max int = %d, min int = %d\n", MAXINT, MININT), 1); 

#define standard trace and pad sizes to reduce scaling or PDF rendering errors:
#This avoids weird aperture settings and replaces them with more standardized values.
#(I'm not sure how photoplotters handle strange sizes).
#Fewer choices here gives more accurate mapping in the final Gerber files.
#units are in inches
use constant TOOL_SIZES => #add more as desired
(
#round or square pads (> 0) and drills (< 0):
    .010, -.001,  #tiny pads for SMD; dummy drill size (too small for practical use, but needed so StandardTool will use this entry)
    .031, -.014,  #used for vias
    .041, -.020,  #smallest non-filled plated hole
    .051, -.025,
    .056, -.029,  #useful for IC pins
    .070, -.033,
    .075, -.040,  #heavier leads
#    .090, -.043,  #NOTE: 600 dpi is not high enough resolution to reliably distinguish between .043" and .046", so choose 1 of the 2 here
    .100, -.046,
    .115, -.052,
    .130, -.061,
    .140, -.067,
    .150, -.079,
    .175, -.088,
    .190, -.093,
    .200, -.100,
    .220, -.110,
    .160, -.125,  #useful for mounting holes
#some additional pad sizes without holes (repeat a previous hole size if you just want the pad size):
    .090, -.040,  #want a .090 pad option, but use dummy hole size
    .065, -.040, #.065 x .065 rect pad
    .035, -.040, #.035 x .065 rect pad
#traces:
    .001,  #too thin for real traces; use only for board outlines
    .006,  #minimum real trace width; mainly used for text
    .008,  #mainly used for mid-sized text, not traces
    .010,  #minimum recommended trace width for low-current signals
    .012,
    .015,  #moderate low-voltage current
    .020,  #heavier trace for power, ground (even if a lighter one is adequate)
    .025,
    .030,  #heavy-current traces; be careful with these ones!
    .040,
    .050,
    .060,
    .080,
    .100,
    .120,
);
#Areas larger than the values below will be filled with parallel lines:
#This cuts down on the number of aperture sizes used.
#Set to 0 to always use an aperture or drill, regardless of size.
use constant { MAX_APERTURE => max((TOOL_SIZES)) + .004, MAX_DRILL => -min((TOOL_SIZES)) + .004 }; #max aperture and drill sizes (plus a little tolerance)
#DebugPrint(sprintf("using %d standard tool sizes: %s, max aper %.3f, max drill %.3f\n", scalar((TOOL_SIZES)), join(", ", (TOOL_SIZES)), MAX_APERTURE, MAX_DRILL), 1);

#NOTE: Compare the PDF to the original CAD file to check the accuracy of the PDF rendering and parsing!
#for example, the CAD software I used generated the following circles for holes:
#CAD hole size:   parsed PDF diameter:      error:
#  .014                .016                +.002
#  .020                .02267              +.00267
#  .025                .026                +.001
#  .029                .03167              +.00267
#  .033                .036                +.003
#  .040                .04267              +.00267
#This was usually ~ .002" - .003" too big compared to the hole as displayed in the CAD software.
#To compensate for PDF rendering errors (either during CAD Print function or PDF parsing logic), adjust the values below as needed.
#units are pixels; for example, a value of 2.4 at 600 dpi = .0004 inch, 2 at 600 dpi = .0033"
use constant
{
    HOLE_ADJUST => -0.004 * 600, #-2.6, #holes seemed to be slightly oversized (by .002" - .004"), so shrink them a little
    RNDPAD_ADJUST => -0.003 * 600, #-2, #-2.4, #round pads seemed to be slightly oversized, so shrink them a little
    SQRPAD_ADJUST => +0.001 * 600, #+.5, #square pads are sometimes too small by .00067, so bump them up a little
    RECTPAD_ADJUST => 0, #(pixels) rectangular pads seem to be okay? (not tested much)
    TRACE_ADJUST => 0, #(pixels) traces seemed to be okay?
    REDUCE_TOLERANCE => .001, #(inches) allow this much variation when reducing circles and rects
};

#Also, my CAD's Print function or the PDF print driver I used was a little off for circles, so define some additional adjustment values here:
#Values are added to X/Y coordinates; units are pixels; for example, a value of 1 at 600 dpi would be ~= .002 inch
use constant
{
    CIRCLE_ADJUST_MINX => 0,
    CIRCLE_ADJUST_MINY => -0.001 * 600, #-1, #circles were a little too high, so nudge them a little lower
    CIRCLE_ADJUST_MAXX => +0.001 * 600, #+1, #circles were a little too far to the left, so nudge them a little to the right
    CIRCLE_ADJUST_MAXY => 0,
    SUBST_CIRCLE_CLIPRECT => FALSE, #generate circle and substitute for clip rects (to compensate for the way some CAD software draws circles)
    WANT_CLIPRECT => TRUE, #FALSE, #AI doesn't need clip rect at all? should be on normally?
    RECT_COMPLETION => FALSE, #TRUE, #fill in 4th side of rect when 3 sides found
};

#allow .012 clearance around pads for solder mask:
#This value effectively adjusts pad sizes in the TOOL_SIZES list above (only for solder mask layers).
use constant SOLDER_MARGIN => +.012; #units are inches

#line join/cap styles:
use constant
{
    CAP_NONE => 0, #butt (none); line is exact length
    CAP_ROUND => 1, #round cap/join; line overhangs by a semi-circle at either end
    CAP_SQUARE => 2, #square cap/join; line overhangs by a half square on either end
    CAP_OVERRIDE => FALSE, #cap style overrides drawing logic
};
    
#number of elements in each shape type:
use constant
{
    RECT_SHAPELEN => 6, #x0, y0, x1, y1, count, "rect" (start, end corners)
    LINE_SHAPELEN => 6, #x0, y0, x1, y1, count, "line" (line seg)
    CURVE_SHAPELEN => 10, #xstart, ystart, x0, y0, x1, y1, xend, yend, count, "curve" (bezier 2 points)
    CIRCLE_SHAPELEN => 5, #x, y, 5, count, "circle" (center + radius)
};
#const my %SHAPELEN =
#Readonly my %SHAPELEN =>
our %SHAPELEN =
(
    rect => RECT_SHAPELEN,
    line => LINE_SHAPELEN,
    curve => CURVE_SHAPELEN,
    circle => CIRCLE_SHAPELEN,
);

#panelization:
#This will repeat the entire body the number of times indicated along the X or Y axes (files grow accordingly).
#Display elements that overhang PCB boundary can be squashed or left as-is (typically text or other silk screen markings).
#Set "overhangs" TRUE to allow overhangs, FALSE to truncate them.
#xpad and ypad allow margins to be added around outer edge of panelized PCB.
use constant PANELIZE => {'x' => 1, 'y' => 1, 'xpad' => 0, 'ypad' => 0, 'overhangs' => TRUE}; #number of times to repeat in X and Y directions

# Set this to 1 if you need TurboCAD support.
#$turboCAD = FALSE; #is this still needed as an option?

#CIRCAD pad generation uses an appropriate aperture, then moves it (stroke) "a little" - we use this to find pads and distinguish them from PCB holes. 
use constant PAD_STROKE => 0.3; #0.0005 * 600; #units are pixels
#convert very short traces to pads or holes:
use constant TRACE_MINLEN => .001; #units are inches
#use constant ALWAYS_XY => TRUE; #FALSE; #force XY even if X or Y doesn't change; NOTE: needs to be TRUE for all pads to show in FlatCAM and ViewPlot
use constant REMOVE_POLARITY => FALSE; #TRUE; #set to remove subtractive (negative) polarity; NOTE: must be FALSE for ground planes

#PDF uses "points", each point = 1/72 inch
#combined with a PDF scale factor of .12, this gives 600 dpi resolution (1/72 * .12 = 600 dpi)
use constant INCHES_PER_POINT => 1/72; #0.0138888889; #multiply point-size by this to get inches

# The precision used when computing a bezier curve. Higher numbers are more precise but slower (and generate larger files).
#$bezierPrecision = 100;
use constant BEZIER_PRECISION => 36; #100; #use const; reduced for faster rendering (mainly used for silk screen and thermal pads)

# Ground planes and silk screen or larger copper rectangles or circles are filled line-by-line using this resolution.
use constant FILL_WIDTH => .01; #fill at most 0.01 inch at a time

# The max number of characters to read into memory
use constant MAX_BYTES => 10 * M; #bumped up to 10 MB, use const

use constant DUP_DRILL1 => TRUE; #FALSE; #kludge: ViewPlot doesn't load drill files that are too small so duplicate first tool

my $runtime = time(); #Time::HiRes::gettimeofday(); #measure my execution time

print STDERR "Loaded config settings from '${\(__FILE__)}'.\n";
1; #last value must be truthful to indicate successful load


#############################################################################################
#junk/experiment:

#use Package::Constants;
#use Exporter qw(import); #https://perldoc.perl.org/Exporter.html

#my $caller = "pdf2gerb::";

#sub cfg
#{
#    my $proto = shift;
#    my $class = ref($proto) || $proto;
#    my $settings =
#    {
#        $WANT_DEBUG => 990, #10; #level of debug wanted; higher == more, lower == less, 0 == none
#    };
#    bless($settings, $class);
#    return $settings;
#}

#use constant HELLO => "hi there2"; #"main::HELLO" => "hi there";
#use constant GOODBYE => 14; #"main::GOODBYE" => 12;

#print STDERR "read cfg file\n";

#our @EXPORT_OK = Package::Constants->list(__PACKAGE__); #https://www.perlmonks.org/?node_id=1072691; NOTE: "_OK" skips short/common names

#print STDERR scalar(@EXPORT_OK) . " consts exported:\n";
#foreach(@EXPORT_OK) { print STDERR "$_\n"; }
#my $val = main::thing("xyz");
#print STDERR "caller gave me $val\n";
#foreach my $arg (@ARGV) { print STDERR "arg $arg\n"; }

Download Details:

Author: swannman
Source Code: https://github.com/swannman/pdf2gerb

License: GPL-3.0 license

#perl 

I am Developer

1611112146

Codeigniter 4 Autocomplete Textbox From Database using Typeahead JS - Tuts Make

Autocomplete textbox search from database in codeigniter 4 using jQuery Typeahead js. In this tutorial, you will learn how to implement an autocomplete search or textbox search with database using jquery typehead js example.

This tutorial will show you step by step how to implement autocomplete search from database in codeigniter 4 app using typeahead js.

Autocomplete Textbox Search using jQuery typeahead Js From Database in Codeigniter

  • Download Codeigniter Latest
  • Basic Configurations
  • Create Table in Database
  • Setup Database Credentials
  • Create Controller
  • Create View
  • Create Route
  • Start Development Server

https://www.tutsmake.com/codeigniter-4-autocomplete-textbox-from-database-using-typeahead-js/

#codeigniter 4 ajax autocomplete search #codeigniter 4 ajax autocomplete search from database #autocomplete textbox in jquery example using database in codeigniter #search data from database in codeigniter 4 using ajax #how to search and display data from database in codeigniter 4 using ajax #autocomplete in codeigniter 4 using typeahead js

Seamus Quitzon

Seamus Quitzon

1595201363

Php how to delete multiple rows through checkbox using ajax in laravel

First thing, we will need a table and i am creating products table for this example. So run the following query to create table.

CREATE TABLE `products` (
 `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
 `name` varchar(255) COLLATE utf8mb4_unicode_ci NOT NULL,
 `description` varchar(255) COLLATE utf8mb4_unicode_ci DEFAULT NULL,
 `created_at` timestamp NULL DEFAULT CURRENT_TIMESTAMP,
 `updated_at` datetime DEFAULT NULL,
 PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci

Next, we will need to insert some dummy records in this table that will be deleted.

INSERT INTO `products` (`name`, `description`) VALUES

('Test product 1', 'Product description example1'),

('Test product 2', 'Product description example2'),

('Test product 3', 'Product description example3'),

('Test product 4', 'Product description example4'),

('Test product 5', 'Product description example5');

Now we are redy to create a model corresponding to this products table. Here we will create Product model. So let’s create a model file Product.php file under app directory and put the code below.

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Product extends Model
{
    protected $fillable = [
        'name','description'
    ];
}

Step 2: Create Route

Now, in this second step we will create some routes to handle the request for this example. So opeen routes/web.php file and copy the routes as given below.

routes/web.php

Route::get('product', 'ProductController@index');
Route::delete('product/{id}', ['as'=>'product.destroy','uses'=>'ProductController@destroy']);
Route::delete('delete-multiple-product', ['as'=>'product.multiple-delete','uses'=>'ProductController@deleteMultiple']);

#laravel #delete multiple rows in laravel using ajax #laravel ajax delete #laravel ajax multiple checkbox delete #laravel delete multiple rows #laravel delete records using ajax #laravel multiple checkbox delete rows #laravel multiple delete

Ruth Nabimanya

Ruth Nabimanya

1620633584

System Databases in SQL Server

Introduction

In SSMS, we many of may noticed System Databases under the Database Folder. But how many of us knows its purpose?. In this article lets discuss about the System Databases in SQL Server.

System Database

Fig. 1 System Databases

There are five system databases, these databases are created while installing SQL Server.

  • Master
  • Model
  • MSDB
  • Tempdb
  • Resource
Master
  • This database contains all the System level Information in SQL Server. The Information in form of Meta data.
  • Because of this master database, we are able to access the SQL Server (On premise SQL Server)
Model
  • This database is used as a template for new databases.
  • Whenever a new database is created, initially a copy of model database is what created as new database.
MSDB
  • This database is where a service called SQL Server Agent stores its data.
  • SQL server Agent is in charge of automation, which includes entities such as jobs, schedules, and alerts.
TempDB
  • The Tempdb is where SQL Server stores temporary data such as work tables, sort space, row versioning information and etc.
  • User can create their own version of temporary tables and those are stored in Tempdb.
  • But this database is destroyed and recreated every time when we restart the instance of SQL Server.
Resource
  • The resource database is a hidden, read only database that holds the definitions of all system objects.
  • When we query system object in a database, they appear to reside in the sys schema of the local database, but in actually their definitions reside in the resource db.

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How to Store Form Data in Database using PHP -2020

In this php code to insert form data into mysql database. I will show you simple way of how to create an html form that stores data in a mysql database using php.

#How to store form data in database using php

  1. Create html form
  2. Create mysql database connection file
  3. Create php file to insert form data into mysql database

https://www.tutsmake.com/php-code-insert-data-into-mysql-database-from-form/

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