Can we output content of a mariaDB table into JSON using the CONNECT Storage Engine ? MariaDB and MySQL are not currently JSON friendly databases. The usage of JSON in MySQL is almost inexistent with the excetion of the explain JSON output and of MariaDB dynamic column dump. There also exist a few udf (in [...]

JavaScript has emerged in the past couple years as the de facto expression of next generation web technologies, and a critical component of HTML5 technologies – along with CSS and JQuery. JavaScript is really ubiquitous – it really is showing up everywhere! There are many other reasons why JavaScript and JS-based tools are becoming the wave of the future. JavaScript is the #1 most-used language on GitHub, and this trend is only going to increase. As one article put it, “JavaScript is the number one …

What is JSON

JSON is an text based, human readable format for transmitting data between systems, for serializing objects and for storing document store data for documents that have different attributes/schema for each document. Popular document store databases use JSON (and the related BSON) for storing and transmitting data.

Problems with JSON in MySQL

It is difficult to inter-operate between MySQL and MongoDB (or other document databases) because JSON has traditionally been very difficult to work with. Up until recently, JSON is just a TEXT document. I said up until recently, so what has changed? The biggest thing is that there are new JSON UDF by Sveta Smirnova, which are part of the MySQL 5.7 Labs releases. Currently the JSON UDF are up to version 0.0.4. While these new UDF are a welcome edition to the MySQL database, they don’t solve the really tough …

What is JSON
JSON is an text based, human readable format for transmitting data between systems, for serializing objects and for storing document store data for documents that have different attributes/schema for each document. Popular document store databases use JSON (and the related BSON) for storing and transmitting data.

Problems with JSON in MySQL
It is difficult to inter-operate between MySQL and MongoDB (or other document databases) because JSON has traditionally been very difficult to work with. Up until recently, JSON is just a TEXT document. I said up until recently, so what has changed? The biggest thing is that there are new JSON UDF by Sveta Smirnova, which are part of the MySQL 5.7 Labs releases. Currently the JSON UDF are up to version 0.0.4. While these new UDF are a welcome edition to the MySQL database, they don't solve the really tough …

New version of JSON UDF functions has been just released. This version introduces two new features.

1. Escape characters in results of JSON_SEARCH function. In previous version if you had document @doc = '{"foo:bar": "baz"}' or '{"foo": {"bar": "baz"}}' return value of JSON_SEARCH(@doc, '"baz"'); was 'foo:bar::' for both. There was no way to distinguish two search paths. Now for the first document JSON_SEARCH returns 'foo\:bar::'
2. Second feature is much bigger. Now JSON functions accessing elements by a key (JSON_CONTAINS_KEY, JSON_EXTRACT, JSON_REPLACE, JSON_REMOVE, JSON_APPEND, JSON_SET, JSON_COUNT) can use alternate keypath syntax: $.key1.key2[arr_index] where $ is root element, .key is key name, [arr_index] is array index. JSON_SEARCH can also return path in this format with escaped $, . and [] symbols.

MariaDB 10.1.3 was recently released, and is available for download here:

https://downloads.mariadb.org/mariadb/10.1.3/

This is the 1st beta, and 4th overall, release of MariaDB 10.1, so there are a lot of new changes, functionalities added, defaults changed, and many bugs fixed (I counted 420 – 117 in 10.1.2 & 637 in 10.1.1, fwiw).

Since it’s beta, I’ll only cover the major changes and additions, and omit covering general bug fixes (feel free to browse them all here).

To me, these are the highlights of the new features:

• Table and Tablespace Encryption.
• …

MariaDB 10.0.16 was recently released (~1.5 months ago on 1/27/2015 – sorry for the delay on my end – I was just extra busy in my spare time recently), and is available for download here:

https://downloads.mariadb.org/mariadb/10.0.16/

This is the seventh GA release of MariaDB 10.0, and 17th overall release of MariaDB 10.0.

For the most part, there are not a whole lot of changes to report for this release, but there are 2 enhancements of note – one being the JSON table type (still *experimental*) and the other a new variable to aid with index statistics calculations on large tables, as well as some security fixes.

Here are the main items of note:

1. Updates to the CONNECT handler (supporting the …

One of the great features of Shard-Query is the ability to use MySQL proxy to access resultsets transparently. While this is a great tool, many people have expressed reservations about using MySQL Proxy, an alpha component in their production environment.

I recognize that this is a valid concern, and have implemented an alternate method of retrieving resultsets directly in the MySQL client, without using a proxy. This means that any node can easily act as the “head” node without any extra daemon, instead of having to run many proxies.

The sq_helper() routine has been checked into the git repository and is available now.

The function takes a few parameters:

• sql to run
• shard-query schema name (empty string or null for default schema)
• schema to store temp table in
• temp table name (where results are sent to)
• return result (boolean, 1 returns …

MySQL meets NoSQL with JSON UDF

I recently got back from FOSDEM, in Brussels, Belgium. While I was there I got to see a great talk by Sveta Smirnova, about her MySQL 5.7 Labs release JSON UDF functions. It is important to note that while the UDF come in a 5.7 release it is absolutely possible to compile and use the UDF with earlier versions of MySQL because the UDF interface has not changed for a long time. However, the UDF should still be considered alpha/preview level of quality and should not be used in production yet! For this example I am using Percona Server 5.6 with the UDF.

That being said, the proof-of-concept that I’m about to present here uses only one JSON function (JSON_EXTRACT) and it has worked well enough in my testing to present my idea here. The JSON functions will probably be GA sometime soon anyway, and this is a useful test of the JSON_EXTRACT function. …

New version of JSON UDF functions has been just released. This is maintenance release which only contains fix for 4 bugs:

74090/19821398 `INSTALL_JSONUDFS` ISSUES A WARNING DUE TO TRUNCATION OF `VERSION_COMPILE_OS`
74091/19692634 `JSON_DEEP_MERGE`: DEEP CRASH IN `MERGE_TREE`
74092/19692628 CRASH WITH SECOND-HAND NULL IN PARAMETERS
74097/19693198 `CREATE_NEW_VALUE`: STACK BUFFER OVERFLOW, %LLD CAN'T FIT IN CHAR[20]

Also 0.3 branch becomes stable branch and no new features will be pushed to this branch in future. Previous stable branch (0.2) removed from MySQL Labs website.

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