Are they really tricks or simply basic techniques combined to create a solution. Before writing these mechanics for using native MySQL to create a compound JSON object, let me point out that the easiest way to get one is to use the MySQL Node.js library, as shown recently in my “Is SQL Programming” blog post.

Moving data from a relational model output to a JSON structure isn’t as simple as a delimited list of columns in a SQL query. Let’s look at it in stages based on the MySQL Server 12.18.2 Functions that create JSON values.

Here’s how you return single row as a JSON object, which is quite straightforward:

SELECT JSON_OBJECT('first_name',c.first_name,'last_name',c.last_name) AS json_result
FROM   contact c
WHERE …

Is SQL, or Structured Query Language, a programming language? That’s a great question! A question that many answer with emphasis: “No, SQL is not a programming language!” There are some who answer yes; and they usually qualify that answer with something like: “SQL is a programming language designed to communicate with relational databases.”

It strikes me that those saying “yes” are saying that SQL is only a collection of interface methods to read from and write to a database engine. Those saying SQL is not a programming language often qualify that a programming language must have conditional logic and iterative structures, which don’t exist in SQL.

There’s a third group that are fence sitters. They decline to say whether SQL is a programming language, but they also say individuals who only write SQL aren’t programmers. That’s a bit harsh from my perspective.

Before …

While I blogged about how to setup Node.js and MySQL almost two years ago, it was interesting when a student ran into a problem. The student said they’d configured the environment but were unable to use Node.js to access MySQL.

The error is caused by this import statement:

const mysql = require('mysql') 

The student got the following error, which simply says that they hadn’t installed the Node.js package for MySQL driver.

internal/modules/cjs/loader.js:638
    throw err;
    ^

Error: Cannot find module 'mysql'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:636:15)
    at Function.Module._load (internal/modules/cjs/loader.js:562:25)
    at Module.require (internal/modules/cjs/loader.js:692:17)
    at require (internal/modules/cjs/helpers.js:25:18)
    at Object. (/home/student/Data/cit325/oracle-s/lib/Oracle12cPLSQLCode/Introduction/query.js:4:15)
    at Module._compile …

MySQL Partitioned Tables

Learning Outcomes

• Learn about List Partitioning.
• Learn about Range Partitioning.
• Learn about Columns Partitioning.
• Learn about Hash Partitioning.
• Learn about Key Partitioning.
• Learn about Subpartitioning.

Lesson Material

MySQL supports partitioning of tables. It supports range, list, hash, and key partitioning. Range partitioning lets you partition based on column values that fall within given ranges. List partitioning lets you partition based on columns matching one of a set of discrete values. Hash partitioning lets you partition based on the return value from a user-defined expression (the result from a stored SQL/PSM function). Key partitioning performs like hash partitioning, but it lets a user select one or more columns from the …

Almost a Ripley’s Believe It or Not. An prior data science student told me that his new IT department setup a Windows component that let him connect his Excel Spreadsheets to their production MySQL database without a password. Intrigued, I asked if it was a MySQL Connector/ODBC Data Source Configuration, or DSN (Data Source Name)?

He wasn’t sure, so I asked him to connect to PowerShell and run the following command:

Get-Item -Path Registry::HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBC.INI\MySQL

It returned something like this (substituting output from one of my test systems):

    Hive: HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBC.INI


Name                           Property
----                           --------
MySQL                          Driver      : C:\Program Files\MySQL\Connector ODBC 8.0\myodbc8w.dll
                               DESCRIPTION : MySQL ODBC Connector
                               SERVER      : …

I’m always updating VMs, and I was gratified to notice that there’s a Fedora arm64 ISO. If you’re interested in it, you can download the Live Workstation from here or the Fedora Server from here.

Unfortunately, I only have macOS running on i7 and i9 Intel Processors. It would be great to hear back how it goes for somebody one of the new Apple M1 chip.

I typically install the workstation version because it meets my needs to run MySQL and other native Linux development tools. However, the server version is also available. Fedora is a wonderful option, as a small footprint for testing things on my MacBookPro.

We had an interesting set of questions regarding the REGEXP comparison operator in MySQL today in both sections of Database Design and Development. They wanted to know the default behavior.

For example, we built a little movie table so that we didn’t change their default sakila example database. The movie table was like this:

CREATE TABLE movie
( movie_id     int unsigned primary key auto_increment
, movie_title  varchar(60)) auto_increment=1001;

Then, I inserted the following rows:

INSERT INTO movie 
( movie_title )
VALUES
 ('The King and I')
,('I')
,('The I Inside')
,('I am Legend');

Querying all results with this query:

SELECT * FROM movie;

It returns the following results:

+----------+----------------+
| movie_id | movie_title    |
+----------+----------------+
|     1001 | The King and I |
|     1002 | I              |
|     1003 | The I Inside   |
|     1004 | I am Legend …

This post explains and demonstrates how to install, configure, and use the MySQL’s ODBC libraries and a DSN (Data Source Name) to connect your Microsoft PowerShell programs to a locally or remotely installed MySQL database. After you’ve installed the MySQL ODBC library, use Windows search field to find the ODBC Data Sources dialog and run it as administrator.

There are four steps to setup, test, and save your ODBC Data Source Name (DSN) for MySQL. You can click on the images on the right to launch them in a more readable format or simply read the instructions.

MySQL ODBC Setup Steps

1. Click the SystemDSN tab to see he view which is …

A student wanted a better example of writing a MySQL Persistent Stored Module (PSM) that maintains transactional scope across a couple tables. Here’s the one I wrote about ten years ago to build the MySQL Video Store model. It looks I neglected to put it out there before, so here it is for reference.

-- Conditionally drop procedure if it exists.
DROP PROCEDURE IF EXISTS contact_insert;

-- Reset the delimiter so that a semicolon can be used as a statement and block terminator.
DELIMITER $$

SELECT 'CREATE PROCEDURE contact_insert' AS "Statement";
CREATE PROCEDURE contact_insert
( pv_member_type         CHAR(12)
, pv_account_number      CHAR(19)
, pv_credit_card_number  CHAR(19)
, pv_credit_card_type    CHAR(12)
, pv_first_name          CHAR(20)
, pv_middle_name         CHAR(20)
, pv_last_name           CHAR(20)
, pv_contact_type        CHAR(12)
, pv_address_type        CHAR(12)
, pv_city                CHAR(30)
, pv_state_province      CHAR(30)
, …

In MySQL, the @@sql_mode parameter should generally use ONLY_FULL_GROUP_BY. If it doesn’t include it and you don’t have the ability to change the database parameters, you can use a MySQL PSM (Persistent Stored Module), like:

Create the set_full_group_by procedure:

-- Drop procedure conditionally on whether it exists already.
DROP PROCEDURE IF EXISTS set_full_group_by;

-- Reset delimter to allow semicolons to terminate statements.
DELIMITER $$

-- Create a procedure to verify and set connection parameter.
CREATE PROCEDURE set_full_group_by()
  LANGUAGE SQL
  NOT DETERMINISTIC
  SQL SECURITY DEFINER
  COMMENT 'Set connection parameter when not set.'
BEGIN

  /* Check whether full group by is set in the connection and
     if unset, set it in the scope of the connection. */
  IF NOT EXISTS
    (SELECT NULL
     WHERE  REGEXP_LIKE(@@SQL_MODE,'ONLY_FULL_GROUP_BY'))
  THEN
    SET SQL_MODE=(SELECT CONCAT(@@sql_mode,',ONLY_FULL_GROUP_BY'));
  END IF; …