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Open Fedora Port 80

with one comment

After installing the LAMP stack on Fedora, you need to open port 80 in the Firewall to access the PHP programs on the Fedora instance from external servers. You can open a firewall port by launching the firewall-config application as the root user with the following syntax:

firewall-config

The firewall-config utility opens the following dialog:

FedoraFirewall1

Click on the Ports tab, and you’ll see the following:

FedoraFirewall2

Click on Add button to add a port exception, and you’ll see the following:

FedoraFirewall3

Enter Port 80 for the Apache server unless you used a different value for the Apache server’s listener port. If you’re not sure open the /etc/httpd/conf/httpd.conf file and check for the following line (default value shown):

Listen 80

Click the OK button to set the port exception. Then, you can connect to the Linux machine with the IP address, a DNS name, or a name you resolve in your local hosts file, like:

http://192.168.2.1/query.php

You can find the IP address of your Fedora image by inspecting the /etc/hosts file or capture a DHCP assigned address with the following command as the root user (or with sudo as a valid sudoer user):

ifconfig -a

It should return the following image, which is based on the data stored in MySQL’s studentdb database, as qualified in yesterday’s blog post:

ExternalWebPage

I hope this helps those setting up a LAMP instance to work with the MySQL database.

Written by maclochlainn

March 29th, 2015 at 12:35 am

Fedora Install LAMP

with one comment

My students wanted an extra credit assignment, so I thought a LAMP configuration and test would be appropriate. The only problem was I hadn’t added it to their course VMware instance. So, here are the instructions to install Apache2, PHP, and MySQLi for a complete LAMP stack when MySQL is already installed.

The post builds on my Fedora Install of MySQL and MySQL Workbench on Fedora posts from last year. It also presumes that you’ve installed a studentdb database but you need to know how to do that let me know (but it hasn’t changed much from the example at the bottom of this old MySQL 5.1 blog post).

You install Apache2 with the following command as the root user, or with the sudo command as a sudoer-list user:

yum install httpd

The following displays the results of starting the yum utility to install httpd, and you need to reply with a y to complete the installation:

Loaded plugins: langpacks, refresh-packagekit
mysql-connectors-community                                  | 2.5 kB  00:00     
mysql-tools-community                                       | 2.5 kB  00:00     
mysql56-community                                           | 2.5 kB  00:00     
pgdg93                                                      | 3.6 kB  00:00     
updates/20/x86_64/metalink                                  |  16 kB  00:00     
updates                                                     | 4.9 kB  00:00     
updates/20/x86_64/primary_db                                |  13 MB  00:04     
(1/2): updates/20/x86_64/updateinfo                         | 1.9 MB  00:02     
(2/2): updates/20/x86_64/pkgtags                            | 1.4 MB  00:01     
Resolving Dependencies
--> Running transaction check
---> Package httpd.x86_64 0:2.4.10-2.fc20 will be installed
--> Processing Dependency: httpd-tools = 2.4.10-2.fc20 for package: httpd-2.4.10-2.fc20.x86_64
--> Processing Dependency: system-logos-httpd for package: httpd-2.4.10-2.fc20.x86_64
--> Running transaction check
---> Package fedora-logos-httpd.noarch 0:21.0.1-1.fc20 will be installed
---> Package httpd-tools.x86_64 0:2.4.10-2.fc20 will be installed
--> Finished Dependency Resolution
 
Dependencies Resolved
 
================================================================================
 Package                  Arch         Version              Repository     Size
================================================================================
Installing:
 httpd                    x86_64       2.4.10-2.fc20        updates       1.2 M
Installing for dependencies:
 fedora-logos-httpd       noarch       21.0.1-1.fc20        fedora         28 k
 httpd-tools              x86_64       2.4.10-2.fc20        updates        79 k
 
Transaction Summary
================================================================================
Install  1 Package (+2 Dependent packages)
 
Total download size: 1.3 M
Installed size: 4.0 M
Is this ok [y/d/N]: y
Downloading packages:
(1/3): fedora-logos-httpd-21.0.1-1.fc20.noarch.rpm          |  28 kB  00:00     
(2/3): httpd-2.4.10-2.fc20.x86_64.rpm                       | 1.2 MB  00:01     
(3/3): httpd-tools-2.4.10-2.fc20.x86_64.rpm                 |  79 kB  00:00     
--------------------------------------------------------------------------------
Total                                              815 kB/s | 1.3 MB  00:01     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction (shutdown inhibited)
  Installing : httpd-tools-2.4.10-2.fc20.x86_64                             1/3 
  Installing : fedora-logos-httpd-21.0.1-1.fc20.noarch                      2/3 
  Installing : httpd-2.4.10-2.fc20.x86_64                                   3/3 
  Verifying  : httpd-2.4.10-2.fc20.x86_64                                   1/3 
  Verifying  : fedora-logos-httpd-21.0.1-1.fc20.noarch                      2/3 
  Verifying  : httpd-tools-2.4.10-2.fc20.x86_64                             3/3 
 
Installed:
  httpd.x86_64 0:2.4.10-2.fc20                                                  
 
Dependency Installed:
  fedora-logos-httpd.noarch 0:21.0.1-1.fc20  httpd-tools.x86_64 0:2.4.10-2.fc20 
 
Complete!

Next, you install php as the root user with the following command:

yum install php

The following displays when you install php, and you need to reply with a y to complete the installation:

Loaded plugins: langpacks, refresh-packagekit
Resolving Dependencies
--> Running transaction check
---> Package php.x86_64 0:5.5.22-1.fc20 will be installed
--> Processing Dependency: php-common(x86-64) = 5.5.22-1.fc20 for package: php-5.5.22-1.fc20.x86_64
--> Processing Dependency: php-cli(x86-64) = 5.5.22-1.fc20 for package: php-5.5.22-1.fc20.x86_64
--> Running transaction check
---> Package php-cli.x86_64 0:5.5.22-1.fc20 will be installed
---> Package php-common.x86_64 0:5.5.22-1.fc20 will be installed
--> Processing Dependency: php-pecl-jsonc(x86-64) for package: php-common-5.5.22-1.fc20.x86_64
--> Running transaction check
---> Package php-pecl-jsonc.x86_64 0:1.3.6-1.fc20 will be installed
--> Processing Dependency: /usr/bin/pecl for package: php-pecl-jsonc-1.3.6-1.fc20.x86_64
--> Processing Dependency: /usr/bin/pecl for package: php-pecl-jsonc-1.3.6-1.fc20.x86_64
--> Running transaction check
---> Package php-pear.noarch 1:1.9.5-6.fc20 will be installed
--> Processing Dependency: php-xml for package: 1:php-pear-1.9.5-6.fc20.noarch
--> Processing Dependency: php-posix for package: 1:php-pear-1.9.5-6.fc20.noarch
--> Running transaction check
---> Package php-process.x86_64 0:5.5.22-1.fc20 will be installed
---> Package php-xml.x86_64 0:5.5.22-1.fc20 will be installed
--> Finished Dependency Resolution
 
Dependencies Resolved
 
================================================================================
 Package               Arch          Version               Repository      Size
================================================================================
Installing:
 php                   x86_64        5.5.22-1.fc20         updates        2.6 M
Installing for dependencies:
 php-cli               x86_64        5.5.22-1.fc20         updates        3.9 M
 php-common            x86_64        5.5.22-1.fc20         updates        1.0 M
 php-pear              noarch        1:1.9.5-6.fc20        updates        343 k
 php-pecl-jsonc        x86_64        1.3.6-1.fc20          updates         34 k
 php-process           x86_64        5.5.22-1.fc20         updates         77 k
 php-xml               x86_64        5.5.22-1.fc20         updates        247 k
 
Transaction Summary
================================================================================
Install  1 Package (+6 Dependent packages)
 
Total download size: 8.2 M
Installed size: 32 M
Is this ok [y/d/N]: y
Downloading packages:
(1/7): php-5.5.22-1.fc20.x86_64.rpm                         | 2.6 MB  00:03     
(2/7): php-cli-5.5.22-1.fc20.x86_64.rpm                     | 3.9 MB  00:03     
(3/7): php-common-5.5.22-1.fc20.x86_64.rpm                  | 1.0 MB  00:00     
(4/7): php-pear-1.9.5-6.fc20.noarch.rpm                     | 343 kB  00:00     
(5/7): php-pecl-jsonc-1.3.6-1.fc20.x86_64.rpm               |  34 kB  00:00     
(6/7): php-process-5.5.22-1.fc20.x86_64.rpm                 |  77 kB  00:00     
(7/7): php-xml-5.5.22-1.fc20.x86_64.rpm                     | 247 kB  00:00     
--------------------------------------------------------------------------------
Total                                              1.1 MB/s | 8.2 MB  00:07     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction (shutdown inhibited)
  Installing : php-cli-5.5.22-1.fc20.x86_64                                 1/7 
  Installing : php-process-5.5.22-1.fc20.x86_64                             2/7 
  Installing : php-xml-5.5.22-1.fc20.x86_64                                 3/7 
  Installing : 1:php-pear-1.9.5-6.fc20.noarch                               4/7 
  Installing : php-common-5.5.22-1.fc20.x86_64                              5/7 
  Installing : php-pecl-jsonc-1.3.6-1.fc20.x86_64                           6/7 
  Installing : php-5.5.22-1.fc20.x86_64                                     7/7 
  Verifying  : php-5.5.22-1.fc20.x86_64                                     1/7 
  Verifying  : php-common-5.5.22-1.fc20.x86_64                              2/7 
  Verifying  : php-cli-5.5.22-1.fc20.x86_64                                 3/7 
  Verifying  : 1:php-pear-1.9.5-6.fc20.noarch                               4/7 
  Verifying  : php-process-5.5.22-1.fc20.x86_64                             5/7 
  Verifying  : php-xml-5.5.22-1.fc20.x86_64                                 6/7 
  Verifying  : php-pecl-jsonc-1.3.6-1.fc20.x86_64                           7/7 
 
Installed:
  php.x86_64 0:5.5.22-1.fc20                                                    
 
Dependency Installed:
  php-cli.x86_64 0:5.5.22-1.fc20        php-common.x86_64 0:5.5.22-1.fc20      
  php-pear.noarch 1:1.9.5-6.fc20        php-pecl-jsonc.x86_64 0:1.3.6-1.fc20   
  php-process.x86_64 0:5.5.22-1.fc20    php-xml.x86_64 0:5.5.22-1.fc20         
 
Complete!

After installing the software, you can set the Apache server to start automatically with the following command:

chkconfig httpd on

However, that command only starts the Apache server the next time you boot the server. You use the following command as the root user to start the Apache server:

apachectl start

You can verify the installation with the following command as the root user:

ps -ef | grep httpd | grep -v grep

It should return:

root      5433     1  0 17:03 ?        00:00:00 /usr/sbin/httpd -DFOREGROUND
apache    5434  5433  0 17:03 ?        00:00:00 /usr/sbin/httpd -DFOREGROUND
apache    5435  5433  0 17:03 ?        00:00:00 /usr/sbin/httpd -DFOREGROUND
apache    5436  5433  0 17:03 ?        00:00:00 /usr/sbin/httpd -DFOREGROUND
apache    5437  5433  0 17:03 ?        00:00:00 /usr/sbin/httpd -DFOREGROUND
apache    5438  5433  0 17:03 ?        00:00:00 /usr/sbin/httpd -DFOREGROUND
apache    5442  5433  0 17:03 ?        00:00:00 /usr/sbin/httpd -DFOREGROUND

and, then verify the listening port with the following command as the root user:

netstat -tulpn | grep :80

It should return the following when both the Apache server is listening on port 80 and the Oracle multi-protocol server is listening on port 8080:

tcp6       0      0 :::80                   :::*                    LISTEN      5433/httpd          
tcp6       0      0 :::8080                 :::*                    LISTEN      1505/tnslsnr

After verifying the connection, you can test it by creating the traditional info.php program file in the /var/www/http directory. The file should contain the following:

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<?php
  phpinfo();
?>

You can test it by opening the Firefox browser and entering the following URL from the Fedora Linux image:

http://localhost/info.php

It should display the typical diagnostic page. This verifies the configuration of the Apache and PHP servers. The next step verifies whether you have the mysqli library to connect to the MySQL database.

You create a mysqli_check.php script, like this:

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<html>
<header>
<title>Static Query Object Sample</title>
<style type="text/css">
  /* HTML element styles. */
  table {background:white;border-style:solid;border-width:3px;border-color:black;border-collapse:collapse;}
  th {text-align:center;font-style:bold;background:lightgray;border:solid 1px gray;}
  td {border:solid 1px gray;}
 
  /* Class tag element styles. */
  .ID {min-width:50px;text-align:right;}
  .Label {min-width:200px;text-align:left;}
</style>
</header>
<body>
<?php
  if (!function_exists('mysqli_init') && !extension_loaded('mysqli')) {
    print 'mysqli not installed.'; }
  else {
    print 'mysqli installed.'; }
?>
</script>
</body>
</html>

You can test it with the following URL from the local browser:

http://localhost/mysqli_check.php

If it’s installed you can skip the next step, but if not you need to run yum in expert mode as follows (the check for php-mysql isn’t really necessary because it’s too old a version but good practice):

[root@localhost etc]# yum shell
Loaded plugins: langpacks, refresh-packagekit
> remove php-mysql
No Match for argument: php-mysql
> install php-mysqlnd
> run
--> Running transaction check
---> Package php-mysqlnd.x86_64 0:5.5.22-1.fc20 will be installed
--> Processing Dependency: php-pdo(x86-64) = 5.5.22-1.fc20 for package: php-mysqlnd-5.5.22-1.fc20.x86_64
--> Running transaction check
---> Package php-pdo.x86_64 0:5.5.22-1.fc20 will be installed
--> Finished Dependency Resolution
 
================================================================================
 Package             Arch           Version               Repository       Size
================================================================================
Installing:
 php-mysqlnd         x86_64         5.5.22-1.fc20         updates         293 k
Installing for dependencies:
 php-pdo             x86_64         5.5.22-1.fc20         updates         141 k
 
Transaction Summary
================================================================================
Install  1 Package (+1 Dependent package)
 
Total download size: 433 k
Installed size: 1.4 M
Is this ok [y/d/N]: y
Downloading packages:
(1/2): php-mysqlnd-5.5.22-1.fc20.x86_64.rpm                 | 293 kB  00:00     
(2/2): php-pdo-5.5.22-1.fc20.x86_64.rpm                     | 141 kB  00:00     
--------------------------------------------------------------------------------
Total                                              427 kB/s | 433 kB  00:01     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction (shutdown inhibited)
  Installing : php-pdo-5.5.22-1.fc20.x86_64                                 1/2 
  Installing : php-mysqlnd-5.5.22-1.fc20.x86_64                             2/2 
  Verifying  : php-pdo-5.5.22-1.fc20.x86_64                                 1/2 
  Verifying  : php-mysqlnd-5.5.22-1.fc20.x86_64                             2/2 
 
Installed:
  php-mysqlnd.x86_64 0:5.5.22-1.fc20                                            
 
Dependency Installed:
  php-pdo.x86_64 0:5.5.22-1.fc20                                                
 
Finished Transaction
> quit

You should note that this also installed PDO. One caveat, before you rerun the mysqli_check.php script from a browser, you need to restart the Apache server. You can do that as the root user with the following syntax:

apachectl restart

You can retest it with the following URL from the local browser:

http://localhost/mysqli_check.php

At this point you should have everything installed to test your connection the MySQL database. As mentioned, this example extends my instructions for installing MySQL on the Fedora instance.

The following query.php file tests your ability to connect to the MySQL database with the mysqli driver, and it uses the studentdb and video store example from my Oracle Database 11g and MySQL 5.6 Developer Handbook:

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<html>
<header>
<title>Static Query Object Sample</title>
<style type="text/css">
  /* HTML element styles. */
  table {background:white;border-style:solid;border-width:3px;border-color:black;border-collapse:collapse;}
  th {text-align:center;font-style:bold;background:lightgray;border:solid 1px gray;}
  td {border:solid 1px gray;}
 
  /* Class tag element styles. */
  .ID {min-width:50px;text-align:right;}
  .Label {min-width:200px;text-align:left;}
</style>
</header>
<body>
<?php
  // Assign credentials to connection.
  $mysqli = new mysqli("localhost", "student", "student", "studentdb");
 
  // Check for connection error and print message.
  if ($mysqli->connect_errno) {
    print $mysqli->connect_error."<br />";
    print "Connection not established ...<br />";
  }
  else {
 
    // Declare a static query.
    $query = "SELECT au.system_user_id, au.system_user_name FROM system_user au" ;
 
    // Loop through a result set until completed.  
    do {
 
      // Attempt query and exit with failure before processing.
      if (!$stmt = $mysqli->query($query)) {
 
        // Print failure to resolve query message.
        print $mysqli->error."<br />";
        print "Failed to resolve query ...<br />";
      }     
      else {
 
        // Print the opening HTML table tag.
        print '<table><tr><th class="ID">ID</th><th class="Label">User Role Name</th></tr>';
 
        // Fetch a row for processing.
        while( $row = $stmt->fetch_row() ) {
 
          // Print the opening HTML row tag.
          print "<tr>";
 
          // Loop through the row's columns.
          for ($i = 0;$i < $mysqli->field_count;$i++) {
            // Handle column one differently.
            if ($i == 0)
              print '<td class="ID">'.$row[$i]."</td>";
            else
              print '<td class="Label">'.$row[$i]."</td>";
          }
          // Print the closing HTML row tag.
          print "</tr>"; 
        }
      }
    } while( $mysqli->next_result());
 
  // Print the closing HTML table tag.
  print "</table>"; 
 
  // Release connection resource.
  $mysqli->close(); }
?>
</script>
</body>
</html>

This should display the following in the browser:

FedoraConfigMySQLPHP

You can see how to open port 80 for the Apache server in yesterday’s blog post. As always, I hope a step-by-step approach without assumptions helps those learning MySQL.

Written by maclochlainn

March 28th, 2015 at 7:41 pm

Lowercase Table Names

with 6 comments

A student posed the question about why table names are case sensitive. That’s because case sensitive table names are the default installation, as qualified in the MySQL documentation. You can verify that with the following query:

SELECT CASE
         WHEN @@lower_case_table_names = 1 THEN
           'Case insensitive tables'
         ELSE
           'Case sensitive tables.'
         END AS "Table Name Status";

The default value returned on Linux is:

+------------------------+
| Table Name Status      |
+------------------------+
| Case sensitive tables. |
+------------------------+
1 row in set (0.00 sec)

The default value for the lower_case_table_names value on the Windows OS is 1 not 0 because you can inadvertently create a lowercase and case sensitive table when you write an INSERT statement and use a lowercase table name. I’ve provided that detail in a reply comment to this blog post.

You can change the default by adding the following parameter in the my.cnf file on Linux or the my.ini file on Windows:

# Make all tables case insensitive.
lower_case_table_names=1

This lets you enter tables in upper or mixed case, and stores them in the data catalog as lowercase table names.

Written by maclochlainn

March 22nd, 2015 at 11:53 am

Querying InnoDB Tables

without comments

Somebody ran into the following error message trying to query the innodb_sys_foreign and innodb_sys_foreign_cols tables from the information_schema database:

ERROR 1227 (42000): Access denied; you need (at least one of) the PROCESS privilege(s) for this operation

It’s easy to fix the error, except you must grant the PROCESS privilege. It’s a global privilege and it should only be granted to super users. You grant the privilege global PROCESS privilege to the student user with the following command:

GRANT PROCESS ON *.* TO student;

Then, you can run this query to resolve foreign keys to their referenced primary key column values:

SELECT   SUBSTRING_INDEX(f.id,'/',-1) AS constraint_name
,        CONCAT(SUBSTRING_INDEX(for_name,'/',-1),'.',SUBSTRING_INDEX(for_col_name,'/',-1)) AS foreign_key_column
,        CONCAT(SUBSTRING_INDEX(ref_name,'/',-1),'.',SUBSTRING_INDEX(ref_col_name,'/',-1)) AS primary_key_column
FROM     innodb_sys_foreign f INNER JOIN innodb_sys_foreign_cols fc
ON       f.id = fc.id
WHERE    SUBSTRING_INDEX(f.for_name,'/',-1) = 'system_user_lab'
ORDER BY CONCAT(SUBSTRING_INDEX(for_name,'/',-1),'.',SUBSTRING_INDEX(for_col_name,'/',-1))
,        CONCAT(SUBSTRING_INDEX(ref_name,'/',-1),'.',SUBSTRING_INDEX(ref_col_name,'/',-1));

It returns the following:

+---------------------+--------------------------------------+------------------------------------+
| constraint_name     | foreign_key_column                   | primary_key_column                 |
+---------------------+--------------------------------------+------------------------------------+
| system_user_lab_fk1 | system_user_lab.created_by           | system_user_lab.system_user_id     |
| system_user_lab_fk2 | system_user_lab.last_updated_by      | system_user_lab.system_user_id     |
| system_user_lab_fk3 | system_user_lab.system_user_group_id | common_lookup_lab.common_lookup_id |
| system_user_lab_fk4 | system_user_lab.system_user_type     | common_lookup_lab.common_lookup_id |
+---------------------+--------------------------------------+------------------------------------+
4 rows in set (0.00 sec)

However, you can get the same information without granting the global PROCESS privilege. You simply use the table_constraints and key_column_usage tables, like this:

SELECT   tc.constraint_name
,        CONCAT(kcu.table_name,'.',kcu.column_name) AS foreign_key_column
,        CONCAT(kcu.referenced_table_name,'.',kcu.referenced_column_name) AS primary_key_column
FROM     information_schema.table_constraints tc JOIN information_schema.key_column_usage kcu
ON       tc.constraint_name = kcu.constraint_name
AND      tc.constraint_schema = kcu.constraint_schema
WHERE    tc.constraint_type = 'foreign key'
AND      tc.table_name = 'system_user_lab'
ORDER BY tc.table_name
,        kcu.column_name;

It prints the same output:

+---------------------+--------------------------------------+------------------------------------+
| constraint_name     | foreign_key_column                   | primary_key_column                 |
+---------------------+--------------------------------------+------------------------------------+
| system_user_lab_fk1 | system_user_lab.created_by           | system_user_lab.system_user_id     |
| system_user_lab_fk2 | system_user_lab.last_updated_by      | system_user_lab.system_user_id     |
| system_user_lab_fk3 | system_user_lab.system_user_group_id | common_lookup_lab.common_lookup_id |
| system_user_lab_fk4 | system_user_lab.system_user_type     | common_lookup_lab.common_lookup_id |
+---------------------+--------------------------------------+------------------------------------+
4 rows in set (0.00 sec)

Hope this helps.

Written by maclochlainn

December 27th, 2014 at 1:18 am

MySQL Non-unique Indexes

with one comment

Somebody wanted to know how to find any non-unique indexes in information_schema of the MySQL. The query takes a session variable with the table name and returns the non-unique indexes by column names. It uses a correlated subquery to exclude the table constraints. A similar query lets you find unique indexes in MySQL. Both queries are in this post.

You set the session variable like this:

SET @sv_table_name := 'member_lab';

You can query the indexes result with the following query:

SELECT   s.table_name
,        s.index_name
,        s.seq_in_index
,        s.column_name
FROM     information_schema.statistics s
WHERE    s.table_name = @sv_table_name
AND      s.non_unique = TRUE
AND      NOT EXISTS
          (SELECT   null
           FROM     information_schema.table_constraints tc
           WHERE    s.table_name = tc.table_name
           AND      s.index_name = tc.constraint_name)
ORDER BY s.table_name
,        s.seq_in_index;

You can also reverse the logic and exclude implicit unique indexes on auto incrementing columns, like

SELECT   s.table_name
,        s.index_name
,        s.seq_in_index
,        s.column_name
FROM     information_schema.statistics s
WHERE    s.table_name = @sv_table_name
AND      s.non_unique = FALSE
AND NOT  s.index_name = 'primary' 
AND      EXISTS
          (SELECT   null
           FROM     information_schema.table_constraints tc
           WHERE    s.table_name = tc.table_name
           AND      s.index_name = tc.constraint_name)
ORDER BY s.index_name
,        s.seq_in_index;

Hope this helps those trying to find non-unique indexes for a table in MySQL.

Written by maclochlainn

December 24th, 2014 at 1:14 am

Popular PHP Frameworks

with 2 comments

My students often ask me about popular PHP frameworks and MySQL approaches. I wish a PHP framework choice was as clear as a JavaScript framework, like AngularJS. Unfortunately, PHP frameworks aren’t that clear cut.

It seems that the most popular PHP frameworks are: Laravel (1st), Phalcon (2nd), and Symphony2 (3rd). I found the following graphic (from December 2013) that highlights popularity by percentage of the market (though I can’t guarantee its accuracy). As far as jobs go, on Dice.com only Laravel had more than 3 positions referring to the framework by name. There were actually 42 PHP developer positions that mention Laravel out of 2,115 PHP developer positions. So, it seems learning a specific framework for PHP doesn’t yet have much market appeal.

PHPFrameworkPopularity-1024x853

While learning the basics of PHP are generic, frameworks expedite process and control pattern implementation. My suggestion to students is to target three to five employers that use a specific framework and start learning how to use the framework. I’d like to get opinions from those in the field whether this is the best advice.

As to MySQL, I suggest they learn native Mysqli and MySQL PDO. Any other suggestions on that from readers? Thanks as always.

Written by maclochlainn

December 23rd, 2014 at 1:55 pm

Using MySQL Workbench

with 2 comments

I’ve been setting up a simplified lab environment to let my students learn use in class. This added content will show them how to do reverse engineering with MySQL Workbench.

It’s a complete Fedora image with MySQL and Oracle Database 11g for the course. The uncompressed image is 14GB and the compressed image is 5.3GB. I chose Fedora because it’s the smallest open source image that supports both environments, and Fedora is the closest to Red Hat and Oracle Unbreakable Linux. I’m inclined to make the instance available generally but haven’t figured out the best way to do that.

Here are the new instructions I’m adding and if you have any input leave it as a comment. ;-)

You connect as the student user, which puts you in the /home/student directory. Once connected to the Fedora OS, you open a Terminal session by clicking on Activities in the upper right hand corner, and then you type terminal in the search box. When you’re in the Terminal session, use the following command to verify that the apply_mysql_lab1.sql file is correct:

cat Data/cit225/mysql/lab1/apply_mysql_lab1.sql

It should display the following commands:

\. /home/student/Data/cit225/mysql/lib/cleanup.sql
\. /home/student/Data/cit225/mysql/lib/create_mysql_store_ri.sql
\. /home/student/Data/cit225/mysql/lib/seed_mysql_store_ri.sql

You can run the apply_mysql_lab1.sql to create the tables in the studentdb database, and seed them with data. Assuming you’re in the same /home/student directory, you connect to the studentdb database with the following syntax:

mysql -ustudent -pstudent studentdb

or, more securely:

mysql -ustudent studentdb -p

Having connected to the studentdb database, you can run the following command:

\. /home/student/Data/cit225/mysql/lab1/apply_mysql_lab1.sql

It creates a Video store image and seeds it with some basic data. You can use the show command to see the tables you’ve created, like:

show tables;

It displays:

+---------------------+
| Tables_in_studentdb |
+---------------------+
| address             |
| common_lookup       |
| contact             |
| contacts            |
| current_rental      |
| item                |
| member              |
| rental              |
| rental_item         |
| street_address      |
| system_user         |
| telephone           |
+---------------------+
12 rows in set (0.00 sec)

After successfully creating and seeding the studentdb database, you can run MySQL Workbench by launching it from the search field (recommended). Alternatively, you can open it from a terminal session with the following command. Unfortunately, a command-line launch links the terminal and the MySQL Workbench processes and closing the terminal will close the MySQL Workbench.

mysql-workbench

Here are the instructions for the lab with MySQL Workbench:

FedoraMySQLWorkbenchHome

  1. The first displayed page of MySQL Workbench is the home page (click on it or any of the others to see the full size image). Click the symbol to the right of the MySQL Workbench title.

MySQL_Lab3_01

  1. After clicking the the symbol, it launches the Startup New Connection dialog. Enter a name for your new connection. I recommend you enter MySQLConnection.

MySQL_Lab3_02

  1. Click the Test Connection button to see if it works.

MySQL_Lab3_03

  1. When you click the Test Connection button, MySQL Workbench prompts you for a password. After entering a password and verifying the connection, click the OK button to test the connection.

MySQL_Lab3_04

  1. Click the OK button to continue.

MySQL_Lab3_05

  1. Click the gray highlighted MySQLConnection connection icon below the MySQL Connection title to launch the MySQL Workbench application.

MySQL_Lab3_03

  1. When you click the gray highlighted MySQLConnection connection icon, MySQL Workbench prompts you for a password. After entering a password and verifying the connection, click the OK button to connect to the MySQL Workbench application.

MySQL_Lab3_06

  1. The MySQL Workbench launches in the default view.

MySQL_Lab3_07

  1. Click on the Database menu option and then the Reverse Engineering… option, as shown in the illustration.

MySQL_Lab3_08

  1. This displays the Set Parameters for Connecting to a DBMS dialog. Click the Stored Connection list of values. Choose the MySQLConnection (if you used my suggestion) or the one you created from the list of values of the Stored Connection element. Click the Next button to continue.

MySQL_Lab3_09

  1. Enter the password and click the OK button to connect to the MySQL database.

MySQL_Lab3_10

  1. This is an in-progress display, it runs waiting for the password and until the step of the wizard completes.

MySQL_Lab3_11

  1. This dialog displays when the MySQL Workbench application connects to the database, retrieves a schema (database) list from the database management system, and checks the common server configuration issues. Click the Next button to move to the next step of the wizard.

MySQL_Lab3_12

  1. This Select Schemas to Reverse Engineer dialog displays any available schemas. You check the schemas that you want. Click the Next button to move to the next step of the wizard.

MySQL_Lab3_09

  1. Enter the password and click the OK button to connect to the MySQL database to retrieve objects from the database management system.

MySQL_Lab3_14

  1. This dialog displays when the MySQL Workbench application retrieves objects from the database. Click the Next button to move to the next step of the wizard.

MySQL_Lab3_15

  1. This dialog displays when the MySQL Workbench application retrieves objects from the schemata and checks the result. Click the Next button to move to the next step of the wizard.

MySQL_Lab3_15

  1. This dialog displays the tables, views, and routines to import. Click the Execute button to move to the next step of the wizard.

MySQL_Lab3_16

  1. This dialog displays the tables, views, and routines to import. Click the Execute button to move to the next step of the wizard.

MySQL_Lab3_17

  1. This dialog displays shows the reverse engineering objects and puts them in the object image. Click the Next button to move to the next step of the wizard.

MySQL_Lab3_18

  1. This dialog displays a summary of reverse engineering objects. Click the Close button to move to the next step of the wizard.

MySQL_Lab3_19

  1. The MySQL Model dialog displays after you complete the reverse engineering process. Click the EER Diagram icon or EER Diagram tab to see visual depiction of the database objects.

MySQL_Lab3_20

  1. The EER Diagram is equivalent to the EER Diagram tab. The Navigator displays the tables as blue rectangles. You can scroll through the Canvas Panel to work with the display of tables and views.

MySQL_Lab3_21

  1. The next image shows EER Diagram with the tables moved for display purposes. Sometimes there are too many relationship lines, MySQL Workbench lets you split the lines so they don’t clutter the diagram.

MySQL_Lab3_22

  1. The next image shows you the Property tab of EER Diagram. You should see that the drawSplit checkbox is checked, which suppresses the bottom-most relationship line from displaying in the EER from display on the Canvas Panel.

You can now save the MySQL Workbench file in the Lab 3 directory.

Written by maclochlainn

September 25th, 2014 at 5:10 pm

MySQL Workbench on Fedora

with 2 comments

The early release of Fedora 20 disallowed installation of MySQL Workbench but the current version allows it. Almost like Tom Cruise’s Edge of Tomorrow without the drama. All you need to do is follow my earlier instructions for installing MySQL on Fedora 20. I’d check your kernel to know whether it’s supported. You can check that with this command:

<shell> uname -r

My Fedora is at the following version:

3.14.8-200.fc20.x86_64

Then, you can install MySQL Workbench with yum, like this:

<shell> sudo yum install mysql-workbench

It generates the following log file, and if you have Oracle 11g XE installed you can ignore the mime-type error:

Loaded plugins: langpacks, refresh-packagekit
Resolving Dependencies
--> Running transaction check
---> Package mysql-workbench-community.x86_64 0:6.1.7-1.fc20 will be installed
--> Processing Dependency: libzip.so.2()(64bit) for package: mysql-workbench-community-6.1.7-1.fc20.x86_64
--> Processing Dependency: libvsqlitepp.so.3()(64bit) for package: mysql-workbench-community-6.1.7-1.fc20.x86_64
--> Processing Dependency: libtinyxml.so.0()(64bit) for package: mysql-workbench-community-6.1.7-1.fc20.x86_64
--> Processing Dependency: liblua-5.1.so()(64bit) for package: mysql-workbench-community-6.1.7-1.fc20.x86_64
--> Processing Dependency: libgtkmm-2.4.so.1()(64bit) for package: mysql-workbench-community-6.1.7-1.fc20.x86_64
--> Processing Dependency: libgdkmm-2.4.so.1()(64bit) for package: mysql-workbench-community-6.1.7-1.fc20.x86_64
--> Processing Dependency: libctemplate.so.2()(64bit) for package: mysql-workbench-community-6.1.7-1.fc20.x86_64
--> Running transaction check
---> Package compat-lua-libs.x86_64 0:5.1.5-1.fc20 will be installed
---> Package ctemplate.x86_64 0:2.2-5.fc20 will be installed
---> Package gtkmm24.x86_64 0:2.24.4-2.fc20 will be installed
---> Package libzip.x86_64 0:0.11.2-1.fc20 will be installed
---> Package tinyxml.x86_64 0:2.6.2-4.fc20 will be installed
---> Package vsqlite++.x86_64 0:0.3.13-3.fc20 will be installed
--> Finished Dependency Resolution
 
Dependencies Resolved
 
================================================================================
 Package                    Arch    Version        Repository              Size
================================================================================
Installing:
 mysql-workbench-community  x86_64  6.1.7-1.fc20   mysql-tools-community   24 M
Installing for dependencies:
 compat-lua-libs            x86_64  5.1.5-1.fc20   updates                158 k
 ctemplate                  x86_64  2.2-5.fc20     fedora                 174 k
 gtkmm24                    x86_64  2.24.4-2.fc20  fedora                 748 k
 libzip                     x86_64  0.11.2-1.fc20  updates                 59 k
 tinyxml                    x86_64  2.6.2-4.fc20   updates                 49 k
 vsqlite++                  x86_64  0.3.13-3.fc20  updates                 58 k
 
Transaction Summary
================================================================================
Install  1 Package (+6 Dependent packages)
 
Total download size: 26 M
Installed size: 119 M
Is this ok [y/d/N]: y
Downloading packages:
(1/7): compat-lua-libs-5.1.5-1.fc20.x86_64.rpm              | 158 kB  00:01     
(2/7): ctemplate-2.2-5.fc20.x86_64.rpm                      | 174 kB  00:01     
(3/7): tinyxml-2.6.2-4.fc20.x86_64.rpm                      |  49 kB  00:00     
(4/7): gtkmm24-2.24.4-2.fc20.x86_64.rpm                     | 748 kB  00:01     
(5/7): vsqlite++-0.3.13-3.fc20.x86_64.rpm                   |  58 kB  00:00     
(6/7): libzip-0.11.2-1.fc20.x86_64.rpm                      |  59 kB  00:02     
(7/7): mysql-workbench-community-6.1.7-1.fc20.x86_64.rpm    |  24 MB  00:08     
--------------------------------------------------------------------------------
Total                                              2.9 MB/s |  26 MB  00:08     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : gtkmm24-2.24.4-2.fc20.x86_64                                 1/7 
  Installing : libzip-0.11.2-1.fc20.x86_64                                  2/7 
  Installing : vsqlite++-0.3.13-3.fc20.x86_64                               3/7 
  Installing : ctemplate-2.2-5.fc20.x86_64                                  4/7 
  Installing : compat-lua-libs-5.1.5-1.fc20.x86_64                          5/7 
  Installing : tinyxml-2.6.2-4.fc20.x86_64                                  6/7 
  Installing : mysql-workbench-community-6.1.7-1.fc20.x86_64                7/7 
Error in file "/usr/share/applications/oraclexe-startdb.desktop": "Application/database" is an invalid MIME type ("Application" is an unregistered media type)
  Verifying  : tinyxml-2.6.2-4.fc20.x86_64                                  1/7 
  Verifying  : compat-lua-libs-5.1.5-1.fc20.x86_64                          2/7 
  Verifying  : ctemplate-2.2-5.fc20.x86_64                                  3/7 
  Verifying  : vsqlite++-0.3.13-3.fc20.x86_64                               4/7 
  Verifying  : mysql-workbench-community-6.1.7-1.fc20.x86_64                5/7 
  Verifying  : libzip-0.11.2-1.fc20.x86_64                                  6/7 
  Verifying  : gtkmm24-2.24.4-2.fc20.x86_64                                 7/7 
 
Installed:
  mysql-workbench-community.x86_64 0:6.1.7-1.fc20                               
 
Dependency Installed:
  compat-lua-libs.x86_64 0:5.1.5-1.fc20     ctemplate.x86_64 0:2.2-5.fc20       
  gtkmm24.x86_64 0:2.24.4-2.fc20            libzip.x86_64 0:0.11.2-1.fc20       
  tinyxml.x86_64 0:2.6.2-4.fc20             vsqlite++.x86_64 0:0.3.13-3.fc20    
 
Complete!

After successfully installing MySQL Workbench, you can launch it with the following command:

<shell> mysql-workbench

It should launch the following MySQL Workbench home page (click on it to see the full size image):

FedoraMySQLWorkbenchHome

Written by maclochlainn

September 13th, 2014 at 12:00 am

MySQL Insert from Query

with 4 comments

While working with an error that my students surfaced in the Oracle Database 12c, I blogged about the limit of using a subquery in an Oracle INSERT statement, and I discovered something when retesting it in MySQL. It was a different limitation. I was also surprised when I didn’t find any mention of it through a Google search, but then I may just not have the right keywords.

The original test case uses a subquery to create a multiple row result set for an INSERT statement. Unfortunately, I discovered that you can’t always embed a UNION or UNION ALL inside a subquery. At least, you can’t when you call the subquery inside an INSERT statement. For example, let’s create a DESTINATION table and then we’ll try to insert records with a query that fabricates a result set.

-- Drop the destination table.
DROP TABLE IF EXISTS destination;
 
-- Create the destination table.
CREATE TABLE destination
( destination_id    int unsigned
, destination_name  varchar(30));

Now let’s try the subquery:

1
2
3
4
INSERT INTO destination
( SELECT 1,'Sample1'
  UNION ALL
  SELECT 2,'Sample2' );

It raises the following error message:

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNION ALL
  SELECT 2,'Sample2' )' at line 3

I wasn’t sure if I missed something. It turned out that I did. While you can put a subquery inside an INSERT statement, you can’t embed it inside a set of parentheses when it contains a UNION ALL set operator. Other statements work with or without parentheses.

1
2
3
4
INSERT INTO destination
  SELECT 1,'Sample1'
  UNION ALL
  SELECT 2,'Sample2';

If somebody has any more to add, I look forward to reading it.

Written by maclochlainn

June 15th, 2014 at 12:19 am

Posted in MySQL,sql

Tagged with

Toad Freeware Page

without comments

While I posted how to install Toad for MySQL Freeware five years ago, I’m always surprised how few people know about it there and consistently updated and improved. You can download Toad for MySQL Freeware or Toad Freeware for Oracle, SQL Server, Sybase, or IBM DB2 at this web site.

MySQLToadHome

You can also download Toad Data Modeler Freeware Edition. Just two notes, while Toad for Oracle Freeware is an MSI file, Toad for MySQL Freeware is a zip file and limited to only a Windows install.

Written by maclochlainn

April 30th, 2014 at 1:46 am