Darwin 13.4.0 Darwin Kernel Version 13.4.0: Sun Aug 17 19:50:11 PDT 2014; root:xnu-2422.115.4~1/RELEASE_X86_64 x86_64

There is a related question.

Dynamic columns allow BINARY values. JSON cannot in general represent binary data. At present, if a dynamic column has a BINARY value then COLUMN_JSON just puts it in quotation marks and sends it. If the document is utf8 then this usually means that the document returned is not valid JSON. Most JSON encoders reject inputs that cannot be encoded with an error but Maria instead returns an invalid document that cannot be decoded using normal JSON libraries.

However, I don't know what the right behavior should be.

Server version: 10.1.13-MariaDB - Homebrew

-- this returns a valid json string

SELECT COLUMN_JSON(COLUMN_CREATE('test','Text "escape"')) AS json;

+----------------------------+

| json                       |

+----------------------------+

| {"test":"Text \"escape\""} |

+----------------------------+

-- this does not return a valid json string

SELECT COLUMN_JSON(COLUMN_CREATE('test','First line\nSecond line')) AS json;

+-----------------------------------+

| json                              |

+-----------------------------------+

| {"test":"First line

Second line"} |

+-----------------------------------+

The valid json output for the last query should be:

+------------------------------------+

| json                               |

+------------------------------------+

| {"test":"First line\nSecond line"} |

+------------------------------------+

github branch: bb-10.0-MDEV-7533

revision-id: 16298d9e82eb507c5e0ca6d097e6a7016582ccbc (mariadb-10.0.33-47-g16298d9e82e)
parent(s): 5e87f49a9927bf3fd0bd9af789bbdd329e4b4416
author: Oleksandr Byelkin
committer: Oleksandr Byelkin
timestamp: 2018-01-22 16:53:10 +0100
message:

MDEV-7533: COLUMN_JSON() doesn't escape control characters in string values

escape all charecters less or equal 0x1F (control symbols)
(shorter sequence are not used to make code simple, long encoding is always legal according to the rfc4627)

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