Archive for the ‘MySQL’ Category
The Good, Bad, & Ugly
My take on the good, the bad, and the ugly of our Winter season, beside all the snow I’ve shoveled and blown to get in and out of my driveway, is:
The Good?
February brought us MySQL 5.6 GA (General Availability) and Ruby 2.0.0-p0. Mega thanks to the MySQL and Ruby teams! By the way, if you’ve always wanted to know a little about Ruby without a great deal of effort, you should check this awesome little 20 minute Ruby tutorial. Naturally, the best Ruby Programming book is a bit dated, and maybe there will be a new one later in the year. If anybody knows whether there’s a new edition forthcoming, I’d appreciate hearing about it! Another more current, Ruby 1.9, book is Programming Ruby 1.9: The Pragmatic Programmers’ Guide.
The Bad?
It seems like a lot of folks who implemented Microsoft SharePoint are rapidly preparing to migrate from SharePoint 2010 to 2013, but what’s unclear is whether they’re upgrading for the features or bug fixes. It does seem many are opting for the Microsoft cloud services, and rumor has it that’s because a little collaboration requires a lot of hardware in the data center. It’s probably a good idea to do some research before implementing Microsoft SharePoint.
The Ugly?
If NBC got the quote right today, President Obama disappointed me by saying, “… I should somehow do a Jedi mind meld with these (republican) folks …” How can the President not know that Star Trek Vulcan’s aren’t in the Star Wars universe? Worse yet, my disappointment with Peter Jackson returns because he is releasing the theatrical version The Hobbit: An Unexpected Journey Bluray and DVD on March 19th and then an extended version later in the year. Ouch!!! He’s getting into my wallet again.
Spring starts later this month and the rumor is that Oracle will release Oracle Database 12c soon. Then, we get Iron Man 3, Star Trek into Darkness, and the Lone Ranger, along with warm weather.
Common Lookup Tables 2
Last October I posted an example and description of a common_lookup
table. It was intended to show how common_lookup
tables support drop down selections in web forms. However, it wasn’t adequate to show how they work with existing data, and the function only supported fresh queries.
This post goes to the next level, and shows how to use foreign keys to preselect values for display in web forms. It also rewrites the prior function so that it supports querying existing data and inserting new data.
Let’s start with data stored in join between two tables – the member
and contact
tables. The internal lookup uses the customers name from the contact
table to find the membership account information in the member
table.
1 2 3 4 5 6 7 8 9 10 11 12 13 | SELECT m.account_number , m.member_type -- A fk to common_lookup table. , m.credit_card_number , m.credit_card_type -- A fk to common_lookup table. , c.first_name , c.middle_name , c.last_name , c.contact_type -- A fk to common_lookup table. FROM member m INNER JOIN contact c ON m.member_id = c.member_id WHERE c.first_name = 'Harry' AND c.middle_name = 'James' AND c.last_name = 'Potter'\G |
It returns the results on the left, while a set of joins against the common_lookup
table returns the results on the right (both use the \G
in SQL Monitor to display the data vertically).
The member_type
, credit_card_type
, and contact_type
columns in the data set on the left hold foreign key values. They’re copies of values found in the primary key column of the common_lookup
table. You have the option of using these values to connect the data through a join or through function calls. A join requires three copies of the common_lookup
table and yields the data displayed on the right above. The query to get the meaningful business information from the common_lookup
table is:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 | SELECT m.account_number , cl1.common_lookup_meaning , m.credit_card_number , cl2.common_lookup_meaning , c.first_name , c.middle_name , c.last_name , cl3.common_lookup_meaning FROM member m INNER JOIN contact c ON m.member_id = c.member_id INNER JOIN common_lookup cl1 ON cl1.common_lookup_id = m.member_type INNER JOIN common_lookup cl2 ON cl2.common_lookup_id = m.credit_card_type INNER JOIN common_lookup cl3 ON cl3.common_lookup_id = c.contact_type WHERE c.first_name = 'Harry' AND c.middle_name = 'James' AND c.last_name = 'Potter'\G |
The data returned from any query is symmetrical, which means all columns return the same number of rows. The results of the preceding query are the business results. Although, they’re not what you’d want to display in a web form that presents the ability to change values, like the member, credit card, or contact types. You need to get that information by using the foreign key as a parameter to a function call, and in this case three function calls. One for each of the foreign keys from the original query results. The result is an asymmetric collection of data would look like the following conceptually with Lily Luna Potter as the customer (note the green row is the symmetrical return set from the preceding query):
The f(x)
represents a generic function call where the x
substitutes for the foreign key value as a lookup key to the primary key value of the common_lookup
table. The function in this case is a query that returns a two column list. One column holds the primary key value of the (common_lookup_id
) and the other holds the customer facing description (from the common_lookup_meaning
column).
These steps describe the process:
- Use the natural key (the user name) to find the data in the
contact
table. - Use the
member_id
foreign key column in thecontact
table to link to the same name column primary key in themember
table by joining the two rows. - Use the foreign keys in the new row (combining columns from the
contact
andmember
tables) as call parameters to a PHP function that returns all possible foreign key values and their business descriptions in a web form.
The vertical choices displayed above map to OPTION
tag elements of an HTML SELECT
tag. The blue highlighted value contains an instruction, Select Type, in the display of an HTML OPTION
tag, and it holds a null as the value of the VALUE
attribute for the OPTION
tag. The other displayed rows are the possible values. The green highlighted value is the currently selected value and the yellow highlighted values are alternate possibilities for an end-user to select. The logic for that process is in the PHP get_common_lookup
function below.
Having discussed the structure of the data and problem, we’ll present the result in a dynamically constructed web form below. The display form shows a member account with customer information.
You should note that the primary and foreign keys aren’t displayed because they’re irrelevant to the business process. Primary and foreign keys only serve to support relationships when we use surrogate keys as the primary key of a table. Only the meaningful information from the common_lookup
table are displayed in the preceding form. Behind the web form, the primary and foreign key values are critical to maintaining anomaly free table data.
Each of the drop downs contains the full selection of possibilities from the common_lookup
table, and an end-user could choose a new value by clicking on any of the drop down fields. For example, the following displays the selection of a type of credit card:
The user can click on the drop down, and then navigate from the selection to a new selection. Assuming we don’t change anything, submitting the form should transmit the foreign key column values. The following shows that’s exactly what it does:
As you can see from the screen shot it works easily. Below is the PHP code for a MySQL credentials file and the get_lookup
function. The function lets you find an existing value or returns a set of unique values for you to choose from.
You should rename the following credentials.php
file as MySQLCredentials.inc
for it to work in the file below it.
Assuming you’ve implemented the credentials.php
file as the MySQLCredentials.inc
file, you can now implement the following file. The get_common_lookup
function returns a <SELECT>
tag with a list embedded of <OPTION>
tags with values; one <OPTION>
tag is selected when the foreign key matches a valid primary key value in the common_lookup
table; and no <OPTION>
tag is selected when the foreign key doesn’t match a a valid primary key value in the common_lookup
table. The last possibility means a user must choose a new valid value for the foreign key column when the foreign key column is constrained as a mandatory or not null column.
The code for the web form is a bit more complex, as shown below. It contains three separate calls to the modified get_common_lookup
function (on lines 104, 111, and 126). Each call to the get_common_lookup
function selects the list of possible values and highlights the value associated with the foreign key value.
Here’s the web form code. You should note that it only returns a single row of data from the query by using a natural key from the contact table.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 | <html> <header> <title>Select Option Sample</title> <style type="text/css"> /* Class tag element styles. */ .box {border:1px solid;padding:0px;width:392px;background-color:silver;} .bottomBox {border-left:1px solid;border-right:1px solid;border-bottom:1px solid;padding:5px;width:380px;background-color:silver;} .middleBox {border:1px solid;padding:5px;width:380px;background-color:silver;} .topBox {border-left:1px solid;border-right:1px solid;border-top:1px solid;padding:5px;width:380px;background-color:silver;} .button {margin:5px;background-color:lightblue;font-weight:bold;align:right;} .clear {clear:left;} .dropDown {min-width:50px;display:block;float:left;text-align:left;color:black;} .formDownLabel {width:90px;display:block;float:left;margin:5px;text-align:right;vertical-align:bottom;color:black;} .formAcrossLabel {width:80px;display:block;float:left;padding-bottom:0px;margin:5px 5px 0px;text-align:left;vertical-align:bottom;font-style:italic;font-size:90%;color:black;} .formInput {min-width:150px;margin:5px;text-align:left;} .formShortInput {width:80px;margin:5px;text-align:left;} .title1 {margin-left:0px;font-weight:bold;font-style:italic;font-size:125%;color:black;} .title2 {margin-left:5px;font-weight:bold;font-style:italic;font-size:105%;color:black;} </style> </header> <body> <?php // Include libraries. include_once("MySQLCredentials.inc"); include_once("library.inc"); // Define a HTML page string. $out = ''; // Declare input variables. $first_name = (isset($_GET['first_name'])) ? $_GET['first_name'] : $first_name = "Harry"; $middle_name = (isset($_GET['middle_name'])) ? $_GET['middle_name'] : $middle_name = "James"; $last_name = (isset($_GET['last_name'])) ? $_GET['last_name'] : $last_name = "Potter"; // Declare output variables. $member_account_number = null; $credit_card_number = null; // Declare lookup input and output (initialized as nulls to suppress warnings) variables. $member_table = 'member'; $member_type = 'member_type'; $member_type_id = null; $credit_card_type = 'credit_card_type'; $credit_card_type_id = null; $contact_table = 'contact'; $contact_type = 'contact_type'; $contact_type_id = null; // Assign credentials to connection. $mysqli = new mysqli(HOSTNAME, USERNAME, PASSWORD, DATABASE); // Check for connection error and print message. if ($mysqli->connect_errno) { print $mysqli->connect_error."<br />"; print "Connection not established ...<br />"; } else { // Initial statement. $stmt = $mysqli->stmt_init(); // Declare a static query. $sql = "SELECT m.account_number\n" . ", m.member_type\n" . ", m.credit_card_number\n" . ", m.credit_card_type\n" . ", c.first_name\n" . ", c.middle_name\n" . ", c.last_name\n" . ", c.contact_type\n" . "FROM member m INNER JOIN contact c\n" . "ON m.member_id = c.member_id\n" . "WHERE c.first_name = ?\n" . "AND c.middle_name = ?\n" . "AND c.last_name = ?\n"; // Prepare statement. if ($stmt->prepare($sql)) { $stmt->bind_param("sss",$first_name,$middle_name,$last_name); } // Attempt query and exit with failure before processing. if (!$stmt->execute()) { // Print failure to resolve query message. print $mysqli->error."<br />"; print "Failed to resolve query ...<br />"; } else { // This query only returns one row, and an empty block follows the while logic. $stmt->bind_result($member_account_number, $member_type_id, $credit_card_number, $credit_card_type_id, $first_name, $middle_name, $last_name, $contact_type_id); while ($stmt->fetch()) {} } } // Print the query form. $out .= '<form method="post" name="myForm" action="submitItemType.php">'; $out .= '<label class="title1">Membership Account Information</label><br />'; $out .= '<div class="box">'; $out .= '<div class="topBox">'; $out .= '<label class="formDownLabel">Account #</label><input class="formInput" type="text" value="'.$member_account_number.'" />'; $out .= '<select name="member_type" size="1" onChange="change(this.form.member_type)">'; // Get dynamic membership type lookup string fragment. $out .= get_common_lookup($member_table, $member_type, $member_type_id); $out .= '</select><br />'; $out .= '<label class="formDownLabel">Credit Card #</label><input class="formInput" type="text" value="'.$credit_card_number.'" />'; $out .= '<select name="credit_card_type" size="1" onChange="change(this.form.credit_card_type)">'; // Get dynamic credit card type lookup string fragment. $out .= get_common_lookup($member_table, $credit_card_type, $credit_card_type_id); // Print the closing HTML table tag. $out .= '</select><br />'; $out .= '</div>'; $out .= '<div class="middleBox">'; $out .= '<label class="formDownLabel"> </label>'; $out .= '<label class="formAcrossLabel">First Name</label><label class="formAcrossLabel">Middle Name</label><label class="formAcrossLabel">Last Name</label><br class="clear" />'; $out .= '<label class="formDownLabel">Customer</label><input class="formShortInput" type="text" value="'.$first_name.'" />'; $out .= '<input class="formShortInput" type="text" value="'.$middle_name.'" />'; $out .= '<input class="formShortInput" type="text" value="'.$last_name.'" /><br />'; $out .= '<label class="formDownLabel">Type</label>'; $out .= '<select style="margin:5px" name="contact_type" size="1" onChange="change(this.form.contact_type)">'; // Get dynamic membership type lookup string fragment. $out .= get_common_lookup($contact_table, $contact_type, $contact_type_id); $out .= '</select><br />'; $out .= '</div>'; $out .= '<div class="bottomBox">'; $out .= '<input class="button" style="margin-left:300px" name="submit" type="submit" value="Submit">'; $out .= '</div>'; $out .= '</form>'; $out .= '</body>'; $out .= '</html>'; print $out; ?> </body> </html> |
The submit button simply runs another web page that prints the actual values for the drop down selections. Here’s the code to print that:
1 2 3 4 5 6 7 8 9 10 11 12 | <html> <head> </head> <body> <?php // Print the surrogate key values for the common_lookup_id column. print "MEMBER_TYPE -> [".$_POST['member_type']."]<br />"; print "CREDIT_CARD_TYPE -> [".$_POST['credit_card_type']."]<br />"; print "CONTACT_TYPE -> [".$_POST['contact_type']."]<br />"; ?> </body> </html> |
I hope this helps those who are interested in sorting how to implement a common_lookup
table.
MySQL Auto Increment
Somebody ran into a problem after reading about the MySQL CREATE
statement and the AUTO_INCREMENT
option. They couldn’t get a CREATE
statement to work with an AUTO_INCREMENT
value other than the default of 1. The problem was they were using this incorrect syntax:
CREATE TABLE elvira ( elvira_id int unsigned PRIMARY KEY AUTO_INCREMENT=1001 , movie_title varchar(60)) ENGINE=InnoDB CHARSET=utf8; |
It raises this error:
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 '=1001 , movie_title varchar(60)) ENGINE=InnoDB CHARSET=utf8' at line 2 |
They concluded that MySQL requires you to assign a default value of 1 as the initial automatic numbering value; then you use the ALTER
statement to change the initial sequence value. That assumption is incorrect. The problem was with their assignment of an overriding AUTO_INCREMENT
value inside the parenthetical list of columns. That assignment needs to occur after the list of columns and constraints, like
CREATE TABLE elvira ( elvira_id int unsigned PRIMARY KEY AUTO_INCREMENT , movie_title varchar(60)) ENGINE=InnoDB AUTO_INCREMENT=1001 CHARSET=utf8; |
It’s not an unlikely mistake since there’s no clear example on either of the referenced web pages (at the time of writing). It would be nice if they were added but I’m of the opinion some of the reference manual pages are too sparse.
After creating the table, you have the generic fix that seems to appear most often as an answer to setting or re-setting the auto numbering sequence of a MySQL table:
ALTER TABLE elvira AUTO_INCREMENT=1001; |
Why would you set the auto numbering sequence to something other than 1? Some designers consider it a best practice to increment from a set point like 101 or 1,001 for your Application Programming Interface (API) and they leave a readily identifiable sequence number set for pre- or post-seeded data in tables. The region of preallocated numbers are typically only used in a few of the tables, in any application, but consistently managing sequences across all tables does sometimes simplifies data diagnostics.
Hope this helps somebody looking for a syntax fix. By the way, you can find it on Page 162 of the Oracle Database 11g & MySQL 5.6 Developer Handbook.
Mountain Lion Pre-MySQL
While I try to contain everything about installing MySQL in a single post that I update from time-to-time, Mac OS X, Mountain Lion (10.8.x), requires some pre-steps. You must install XCode, and the Command Line Tools. This post provides the screen shots and step-by-step instructions.
Before you can do any of these steps, you must connect to the Apple Store and download XCode. Dependent on your internet speed this may take some time. Generally, it’s an hour or less.
- After installing XCode, click the Rocket Spaceship in the Mac Dock to launch a view of your Applications. Launch XCode by clicking on the hammer overlaying the blue background XCode icon shown below.
- After launching XCode, click the Install button on the lower right of the System Component Installation screen shown below.
- You’re prompted for your default user (actually a sudoer authorized user) password. Enter it in the dialog and click the OK button to continue.
- After entering the valid credentials and a couple minutes, you should see the System Component Installation screen shown below. Click the Start Using XCode button to continue.
- Inside XCode, click on the XCode menu option and select the Preferences menu option, as shown below.
- You should be on the General tab of XCode’s Preferences dialog. Click on the Downloads tab.
- You should see three choices (at the time of writing) in the Downloads tab. As shown, select the Command Line Tools item. It should take only a couple minutes to download. Click the Install button to continue.
- The Install button disappears and is replaced by an Installed label when the Command Line Tools are installed. You should see the following screen shot.
After completing these steps, return to the other post to install and configure MySQL. While it seems this exists already as content on Apple’s site, it seems some folks wanted me to add it with the step-by-step screen shots.
MySQL Database Triggers
One of the students wanted an equivalent example to an Oracle DML trigger sample that replaces a white space in a last name with a dash for an INSERT
statement. Apparently, the MySQL trigger example in the Oracle Database 11g and MySQL 5.6 Developer Handbook was a bit long. I have to agree with that because the MySQL DML trigger demonstrated cursors and loops in the trigger code.
Triggers can be statement- or row-level actions. Although some databases let you define statement-level triggers, MySQL doesn’t support them. MySQL only supports row-level triggers. Row-level triggers support critical or non-critical behaviors. Critical behavior means the trigger observes an insert, update, or delete that must be stopped, which means it raises an error. Non-critical behavior means the trigger observes a DML statement and logs it or implements a change during the context of the DML activity.
The first example shows you non-critical behavior. It observes an attempt to enter a two-part last name, and replaces the white space with a dash (you can find help on MySQL Regular Expressions in this other post). This means the trigger ensures compliance on how names are entered in the database, which should be protected in the web form (through JQuery or JavaScript) and the database.
DELIMITER $$ DROP TRIGGER IF EXISTS contact_insert$$ CREATE TRIGGER contact_insert BEFORE INSERT ON contact FOR EACH ROW BEGIN IF new.last_name REGEXP '^.* .*$' THEN SET new.last_name := REPLACE(new.last_name,' ','-'); END IF; END; $$ DELIMITER ; |
The problem with implementing a non-critical trigger is that the database performs the work but clerks entering the data don’t learn the business rule. A critical trigger simply disallows non-conforming data entry. The next program shows a critical behavior with an UPDATE
statement row-level trigger. After all, won’t a data entry clerk update the entry with a white space after the INSERT
statement didn’t?
Yes, that was a rhetorical question. Spelling out the business rule in the UPDATE
statement row-level trigger should educate the persistent errant behavior. While letting the INSERT
statement row-level trigger manage the behavior probably saves time for most end-users who make a casual mistake.
DELIMITER $$ DROP TRIGGER IF EXISTS contact_update$$ CREATE TRIGGER contact_update BEFORE UPDATE ON contact FOR EACH ROW BEGIN IF new.last_name REGEXP '^.* .*$' THEN SIGNAL SQLSTATE '42000'; END IF; END; $$ DELIMITER ; |
Somebody wanted to know why I choose SQLSTATE
42000. That’s because it signals an error in the SQL statement, and that’s the closest existing SQLSTATE
to the actual behavior that exists. Moreover, the error identified by the critical trigger signals non-compliance with the application’s SQL standards that protects the data.
Hopefully, this helps somebody looking for a MySQL database trigger example that raises an exception. The example works with MySQL 5.5 forward because the critical trigger uses the SIGNAL
feature, which was introduced in MySQL 5.5. Another article shows you how to leverage MyISAM tables to create a logging mechanism for critical event triggers, and you click this link to the MySQL Triggers with Logging blog entry.
Common Lookup Tables 1
My students wanted an example of how to use a lookup table in the database. I thought it would be a great idea to create a simple example like this one. You can read further on my second post about common lookup tables.
A lookup table is a generalization that holds lists of values that support end-user selections. The following example uses a combination of the common_lookup_table
and common_lookup_column
columns to identify sets of value for drop down lists. The end-user selects a value from the list to identify a unique row, and returns a common_lookup_id
surrogate key value.
The sample code uses the table defined in the previous illustration. It uses a simple HTML drop down list, a PHP library.inc
file, and an HTML display form. Below is the drop down selection set for a table and column value.
The drop down list code uses an insecure and trivial GET
method to keep the example simple, as shown below:
<html> <header> <title>Select Option Sample</title> <style type="text/css"> /* Class tag element styles. */ .label {min-width:200px;text-align:left;} .title {font-weight:bold;font-style:italic;font-size:125%;} </style> </header> <body> <?php // Include libraries. include_once("library.inc"); // Declare input variables. $table_name = (isset($_GET['table_name'])) ? $_GET['table_name'] : $table_name = "item"; $column_name = (isset($_GET['column_name'])) ? $_GET['column_name'] : $column_name = "item_type"; // Call function. get_lookup($table_name, $column_name); ?> </body> </html> |
The library.inc
file contains the logic to use a PHP prepared statement to read and render a SELECT
HTML tag. It uses OPTION
tags for all values in the drop down list. The values for the OPTION
tag are the surrogate key values from the common_lookup_id
column of the common_lookup
table, and text elements are the descriptive values from the common_lookup_meaning
column.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 | <?php /* || Program Name: library.inc */ function get_lookup($table_name, $column_name) { // 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 { // Initial statement. $stmt = $mysqli->stmt_init(); // Declare a static query. $sql = "SELECT cl.common_lookup_id\n" . ", cl.common_lookup_meaning\n" . "FROM common_lookup cl\n" . "WHERE common_lookup_table = ?\n" . "AND common_lookup_column = ?\n" . "ORDER BY 2"; // Prepare statement. if ($stmt->prepare($sql)) { $stmt->bind_param("ss",$table_name,$column_name); } // Loop through a result set until completed. do { // Attempt query and exit with failure before processing. if (!$stmt->execute()) { // Print failure to resolve query message. print $mysqli->error."<br />"; print "Failed to resolve query ...<br />"; } else { // Fetch a row for processing. $result = $stmt->get_result(); // Print the opening select tag. print '<form method="post" name="myForm" action="submitItemType.php">'; print '<div class="title">Select unique from list:</div>'; print '<select name="item_type" size="1" onChange="change(this.form.item_type)">'; print "<option class=label value='' selected>Select </option>"; // Read through the rows of the array. while( $row = $result->fetch_array(MYSQLI_NUM) ) { print "<option class=label value='".$row[0]."'>".$row[1]."</option>"; } } } while($stmt->next_result()); // Print the closing HTML table tag. print '</select>'; print '<input name="submit" type="submit" value="Submit">'; print '</form>'; // Release connection resource. $mysqli->close(); } } ?> |
The display form action calls the submitItemType.php
program, which displays the value from the OPTION
tag selected in the prior form. The code for the display is:
<html> <head> </head> <body> <?php print "ITEM_TYPE -> [".$_POST['item_type']."]"; ?> </body> </html> |
It generates:
Hope this helps illustrate the value of and mechanics of lookup tables. As mentioned above, there’s a newer post on how to leverage common_lookup
tables with more working code.
Open World 2012
In prior years a daily update from Open World was possible, but this year my schedule was too full to support it. This is my compendium of thoughts about MySQL Connect, JavaOne, and Open World 2012.
MySQL Connect was great – good sessions re-enforcing the positive investments Oracle is making in the product. I’ll leave to others to qualify changes in what elements of technology are opened or closed along the road to a better MySQL. The announcement of Connector/Python 1.0 GA on Saturday was great news and as a community we owe a lot to Greet Vanderkelen.
NoSQL is a hot topic along with using JSON objects and it was interesting hearing of some unequal testing paradigms to position non-Oracle solutions to be “better” than Oracle solutions. Naturally, the MongoDB was the elephant in the room during those conversations. Some of the discussions seemed more like political rants than technical dialog. A great spot to start with NoSQL and JSON would be downloading Oracle’s MySQL 5.6 Release Candidate.
There were also more PostgreSQL conversations this year and fairly accurate comparisons between it and Oracle or MySQL from folks. It certainly looks like it may gain more ground.
Java 7 is awesome, and my favorite feature is clearly NIO2, reinforced at JavaOne. NIO2 brings static methods to interactions with external directory and file sources. It removes directories from the files class, which is long overdue. The nature of those static methods also happen to fit within the definition of Java code that lives inside the Oracle database and gives me a whole host of thoughts about potential in Oracle Database 12c.
Larry Ellison’s keynote was impressive because it gives us a clear vision of Oracle’s direction and Duncan Davies captured the keynote well in his blog. The continued presence of Red Hat and VMWare offers interesting reality checks to their key contributions to world wide implementation of the Oracle technical stack.
Issues that seem most critical to those I’ve chatted with are storage, security, tools, and development languages. A nice update on security can be found in the new edition of Hacking Exposed 7: Network Security Secrets & Solutions (7th Edition).
On the forthcoming Oracle 12c release, Information Week just released a good summary view. The introduction of the R programming language on the Exadata Server leads me to wonder about what uses may magically appears in Oracle Enterprise Manager down the road. The TIOBE Index for September 2012 doesn’t list the R language in the top 20 programming languages but there’s always the future. No mention of Erlang programming language at any of the conferences that I caught but it’s inevitably on the horizon as application servers evolve.
Now we wait for the Oracle Database 12c release, which looks like something in the very short term. Perhaps right after the holidays …
MySQL Workbench Book
Finally, I finished writing the MySQL Workbench book. It’ll be available next spring. Now it’s time to leave for the plane, fly to San Francisco, and see everyone at MySQL Connect.
I look forward to meeting folks, I’ll be presenting after MySQL Connect for those staying for Oracle Open World. My presentation is at Oracle Develop on Monday, 10/1/12 from 16:45 – 17:45, in the Marriott Marquis – Foothill F. As I mentioned in an earlier post, you can probably catch me in Moscone West at the bookstore. The publisher requests we attend book signings. 😉
Unfortunately as a speaker I need to convert my Keynote to Powerpoint, and had to purchase, install, and update Microsoft Office 2011 on my Mac. Open Office and Keynote weren’t on the approved list, alas …
Update: The book published 4/9/2013 (a bit of a delay from completing the write, eh?). It’s available on Safari as of yesterday.
MySQL 5.0 migration bug
At present, you can’t use the MySQL Workbench migration tool to migrate MySQL 5.0 to MySQL 5.5, as documented in Bug 66861. The only documentation reference that I could find that references the mysql.proc
table. Since the physical definition of the mysql.proc table changes across the MySQL 5.0, 5.1, and 5.6 releases, I modified my documentation Bug 66886 to suggest providing online documentation (as a feature request) for the mysql
, information_schema
, and performance_schema
tables across all releases.
The actual definition of the mysql.proc
table for MySQL 5.0.91 holds 16 columns not 20 columns as presently expected by the MySQL Workbench migration tool, and is summarized below:
Field | Type | Null | Key |
---|---|---|---|
db | char(64) | NO | PRI |
name | char(64) | NO | PRI |
type | enum(‘FUNCTION’,’PROCEDURE’) | NO | PRI |
specific_name | char(64) | NO | |
language | enum(‘SQL’) | NO | SQL |
sql_data_access | enum(‘CONTAINS_SQL’,…) | NO | CONTAINS_SQL |
is_deterministic | enum(‘YES’,’NO’) | NO | NO |
security_type | enum(‘INVOKER’,’DEFINER’) | NO | DEFINER |
param_list | blob | NO | |
returns | char(64) | NO | |
body | longblob | NO | |
definer | char(77) | NO | |
created | timestamp | NO | CURRENT_TIMESTAMP |
modified | timestamp | NO | 0000-00-00 00:00:00 |
sql_mode | set(‘REAL_AS_FLOAT’,…) | NO | |
comment | char(64) | NO |
I found out about the issue through a comment on my blog from Marc, who was trying to migrate his production instance. I hope this provides a heads-up to anybody else attempting to migrate a MySQL 5.0 database to a MySQL 5.5. The good news is that the MySQL Workbench team appears to be actively working the issue.
Bulk Transfer Works
As many already know, I’ve been trying to get the MySQL Workbench migration feature working between Microsoft SQL Server 2012 and MySQL 5.5. There are a number of features added to the 5.2.43 point release, and one led me to believe that the Migration tool expects to find the data in a schema of its own, as opposed to the dbo
schema. Having made that change in Microsoft SQL Server, it did appear to have a positive impact on the migration and when I corrected a character set mismatch it worked perfectly!
MySQL Workbench successfully migrated the schema and table but failed to migrate the data because of a character set mismatch. I updated Bug 66516 the log file from the character set mismatch before I retyped all 9 test rows to make sure they were in a latin1
character set.
I shortened the original log file because the actual log had over 2,000 blanks line :-(. That’s probably something that should be fixed in the code too.
Starting... Prepare information for data copy... Prepare information for data copy done Create shell script for data copy... Table copy script written to C:\Users\McLaughlinM\Desktop\copy_migrated_tables.cmd Create shell script for data copy done Determine number of rows to copy.... Counting number of rows in tables... wbcopytables.exe --count-only --passwords-from-stdin --odbc-source=DSN=SQL Server ODBC;DATABASE=;UID=sa --table [studentdb] [studentdb].[conquistador] 18:29:13 [INF][ copytable]: Opening ODBC connection to 'DSN=SQL Server ODBC;DATABASE=;UID=sa;PWD=XXX' 18:29:14 [INF][ copytable]: ODBC connection to 'DSN=SQL Server ODBC;DATABASE=;UID=sa;PWD=' opened 9 total rows in 1 tables need to be copied: - [studentdb].[studentdb].[conquistador]: 9 Determine number of rows to copy finished Copy data to target RDBMS.... Migrating data... wbcopytables.exe --odbc-source=DSN=SQL Server ODBC;DATABASE=;UID=sa --target=student@mclaughlinsql:3306 --progress --passwords-from-stdin --thread-count=1 --table [studentdb] [studentdb].[conquistador] `studentdb` `conquistador` [conquistador_id], [conquistador], [actual_name], [nationality] `studentdb`.`conquistador`:Copying 4 columns of 9 rows from table [studentdb].[studentdb].[conquistador] ERROR: `studentdb`.`conquistador`:Inserting Batch: Incorrect string value: '\x9Acak' for column 'actual_name' at row 7 `studentdb`.`conquistador`:Finished copying 0 rows in 0m00s 29:15 [INF][ copytable]: Opening ODBC connection to 'DSN=SQL Server ODBC;DATABASE=;UID=sa;PWD=XXX' 29:16 [INF][ copytable]: ODBC connection to 'DSN=SQL Server ODBC;DATABASE=;UID=sa;PWD=' opened 29:16 [INF][ copytable]: Connecting to MySQL server at mclaughlinsql:3306 with user student 29:16 [INF][ copytable]: Connection to MySQL opened Copy helper has finished Data copy results: - `studentdb`.`conquistador` has FAILED (0 of 9 rows copied) 0 tables of 1 were fully copied Copy data to target RDBMS finished Tasks finished with warnings and/or errors, view the logs for details Finished performing tasks. |
Originally, I thought the failure was due to the extended ASCII characters in the Microsoft SQL Server table. It still failed when I took all of the extended characters out. However, Alfredo suggested it was a character set issue, which is obvious when I looked more closely at the log – '\x9Acak'
is clearly an incorrect string. I retyped the INSERT
statement for the nine rows and it worked perfectly. Naturally, I’ve updated open Bug 66516 with the log file.
If you’re curious about the Microsoft SQL Server configuration check this post.