I found that using Dremio to connect to my MySQL database, some databases are not displayed in Dremio, including “information_schema” and “sys”. Among them, “information_schema” is not displayed, which is understandable because it is a system database, but sys is a database I created myself, but it happens to be called sys, but it is also not displayed in Dremio. Is this normal behavior? @balaji.ramaswamy
Is there any setting that may allow me to change this behavior?
@bigfacewo Looks like sys is by default a system database, see my show databases command output
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| testjson |
+--------------------+
5 rows in set (0.08 sec)
mysql>
Let me see what SQL Dremio sends to MySQL for discovery and get back to you
@bigfacewo Dremio excludes hidden database, by default sys is a system generated database and is hidden, when you say you created a database called sys, did you first drop the system generated one? Is the sys database you created a hidden schema
@bigfacewo Just added my local mysql database and as expected no “sys”, when I look at sys database table via mysql I see a lot of system tables (101 tables), sample below so wondering how you were abe to create your own sys?
mysql> use sys;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> show tables;
+-----------------------------------------------+
| Tables_in_sys |
+-----------------------------------------------+
| host_summary |
| host_summary_by_file_io |
| host_summary_by_file_io_type |
| host_summary_by_stages |
| host_summary_by_statement_latency |
| host_summary_by_statement_type |
| innodb_buffer_stats_by_schema |
| innodb_buffer_stats_by_table |