Copy the following sql statements in a file called `preAlterTables.sql` and replace all occurences of `vikunja` with
the name of your database:
{{<highlightsql>}}
use information_schema;
SELECT concat("ALTER DATABASE `",table_schema,"` CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_ci;") as _sql
FROM `TABLES` where table_schema like 'vikunja' and TABLE_TYPE='BASE TABLE' group by table_schema;
SELECT concat("ALTER TABLE `",table_schema,"`.`",table_name,"` CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;") as _sql
FROM `TABLES` where table_schema like 'vikunja' and TABLE_TYPE='BASE TABLE' group by table_schema, table_name;
SELECT concat("ALTER TABLE `",table_schema,"`.`",table_name, "` CHANGE `",column_name,"``",column_name,"` ",data_type,"(",character_maximum_length,") CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci",IF(is_nullable="YES"," NULL"," NOT NULL"),";") as _sql
FROM `COLUMNS` where table_schema like 'vikunja' and data_type in ('varchar','char');
SELECT concat("ALTER TABLE `",table_schema,"`.`",table_name, "` CHANGE `",column_name,"``",column_name,"` ",data_type," CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci",IF(is_nullable="YES"," NULL"," NOT NULL"),";") as _sql
FROM `COLUMNS` where table_schema like 'vikunja' and data_type in ('text','tinytext','mediumtext','longtext');