Created attachment 145128 [details]
zip with 4 files to reproduce the problem

zipped file with 4 files to reproduce the problem : 

1. Dump20180923 : the file to be imported into MySQL (with mysqldump)
2. TestCJ8 on localhost : the LO Base file 
3. testcj8NOTOK : screenshot with Connector/J 8.0.12
4. testcj8OK :    screenshot with Connector/J 5.1.46

I can connect to several of my own remote mysql instance databases via the 8.0.12 Connector/J on MacOS, and LibreOffice

Version: 6.2.0.0.alpha0+
Build ID: 0b06762ff19a804d3b86167ae3012811662412f1
CPU threads: 4; OS: Mac OS X 10.13.6; UI render: default; 
Locale: fr-FR (fr_FR.UTF-8); Calc: threaded


so the problem could be due to:

- some specific configuration of your database ;
- a duplication of connector/J JAR files added to the classpath in LibreOffice, i.e. you have two different Connector/J jar files added via the classpath configurator dialog (Tools > Options > Advanced > Add Jar archive) ?

I can however reproduce the error message

"The data content could not be loaded"

with tables or views that contain a datetime definition, such as the one below:

CREATE TABLE `AC` (
  `bid` int(10) NOT NULL AUTO_INCREMENT,
  `Ac` varchar(100) COLLATE utf8_unicode_ci DEFAULT NULL,
  `Cur` varchar(3) COLLATE utf8_unicode_ci NOT NULL,
  `dt` datetime DEFAULT NULL,
  PRIMARY KEY (`bid`),
  KEY `cur` (`Cur`)
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci

I also see this same error message with server side views containing calculated dates such as this one :

CREATE VIEW `natpha_ddl` AS 
select `oldfmpro`.`File_Num` AS `file_num`,
`oldfmpro`.`Owner1` AS `Owner1`,
`oldfmpro`.`Filing_Num` AS `filing_num`,
`oldfmpro`.`Filing_Date1` AS `filing_date1`,
`oldfmpro`.`Prio_FF_Date1` AS `Prio_FF_Date1`,
if(((`oldfmpro`.`Prio_FF_Date1` + interval 30 month) is not null),
(`oldfmpro`.`Prio_FF_Date1` + interval 30 month),
(`oldfmpro`.`Filing_Date1` + interval 30 month)) AS `NATPHA` from `oldfmpro` 
where ((`oldfmpro`.`Filing_Num` is not null) 
and (`oldfmpro`.`Ctry_Short` = 'WO') 
and (`oldfmpro`.`IngJur` like '%ajt%') 
and (`oldfmpro`.`Filing_Date1` >= (curdate() + interval -(30) month))) 
order by 
if(((`oldfmpro`.`Prio_FF_Date1` + interval 30 month) is not null),
(`oldfmpro`.`Prio_FF_Date1` + interval 30 month),
(`oldfmpro`.`Filing_Date1` + interval 30 month))

Another example, this view also produces the same error message :

CREATE VIEW `classifier_list` AS 
select `classifier`.`ID` AS `classifier_ID`,`classifier`.`matter_ID` AS `matter_ID`,`classifier_type`.`type` AS `type`,
if(`classifier`.`value_ID`,
`classifier_value`.`value`,
`classifier`.`value`) AS `value` 
from (`classifier` left join (`classifier_type` join `classifier_value`) on(((`classifier`.`type_code` = `classifier_type`.`code`) 
and (`classifier`.`value_ID` = `classifier_value`.`ID`))))

Testing with Connector/J 5.1.47 shows all the required views containing calculated /conditional values and tables containing datetime fields.

This could be a problem with the Connector/J and not LibreOffice, in which case this report will be closed as NOTOURBUG.

Ideally, the connector would need to be tested in a non-LO environment to see whether the same or similar behaviour is observed.

Testing with RazorSQL 8.0.8 and the Connector/J 8.0.12 jar, I don't experience any of the problems that I see with LibreOffice

Alex: sorry I can't do anything for the moment because my local build has failed since 4 days. It's gtk3 related but even Caolán doesn't have any hint. He transferred the pb to Pranav.

I created the table from comment 3, then tried Mysql connection with JDBC mode, no pb to open the table.
Can't help here, uncc myself.

I did some additional research on this problem : it appears when trying to access a view which contains a CAST as DATE (or TIME) function on a DATETIME (or TIMESTAMP) column. 

Here is a short sample : 

1. create a table with a datetime column : 
CREATE TABLE `dt` (`datetime1` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (`datetime1`)) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

2. insert a value :
INSERT INTO `testcj8`.`dt` (`datetime1`) VALUES ('2018-11-11 11:11:11');

3. create a view on this table, with a "cast as date" function on the datetime column :
CREATE VIEW `view-dt` AS select `dt`.`datetime1` AS `datetime1`, cast(`dt`.`datetime1` as date) AS `date1`, cast(`dt`.`datetime1` as time) AS `time1` from `dt`;

4. access this view : SELECT * FROM `view-dt`;

- If LO base is connected to MySQL with MySQL Connector/J 5, there is no problem.
- If LO base is connected to MySQL with MySQL Connector/J 8, there is a  problem : msg "the data could not be loaded".

Please note that the select statement used to create the view can be successfully executed with both connectors !!!

I just upgraded LO to 6.3.0.4, and now the intial problem also happens with the
Connector/J 5.1.46.

I get additional details in the error  message "the data could not be loaded" : 
SQL Status: S1009
Parameter index out of range (1 > number of parameters, which is 0).

Is this problem related to bug 118112 (having the same error message) ?

jnplg: if the problem indeed appeared with LibreOffice version 5.4, you could try to bibisect it:
https://wiki.documentfoundation.org/QA/Bibisect
https://wiki.documentfoundation.org/QA/Bibisect/Windows

For the repository you can use bibisect-win32-5.4. If it turns out the problem is in the oldest commit after all, try bibisect-win32-5.3 next

I do no longer encounter the intial problem.
I applied the solution that is proposed for bug 118112, and the problem is now solved.

(In reply to jnplg from comment #14)
> I do no longer encounter the intial problem.
> I applied the solution that is proposed for bug 118112, and the problem is
> now solved.

What does it mean. The bug doesn't exist any moe? Should we close this one to "Worksforme"?

Hello Robert,
 
My understanding is that this bug is a duplicate of bug 118112, and may be closed as such.

*** This bug has been marked as a duplicate of bug 118112 ***