It is much harder to produce EXPLAIN FORMAT=JSON output than tabular format output.
IIRC, MySQL supports EXPLAIN FORMAT=JSON FOR CONNECTION, but the output lacks some details
Because of the above, we can start by supporting a tabular form in EXPLAIN FOR CONNECTION.
Can we print ANALYZE [ FORMAT=JSON] for the other thread?
Sergei Petrunia
added a comment - Considerations:
It is much harder to produce EXPLAIN FORMAT=JSON output than tabular format output.
IIRC, MySQL supports EXPLAIN FORMAT=JSON FOR CONNECTION, but the output lacks some details
Because of the above, we can start by supporting a tabular form in EXPLAIN FOR CONNECTION.
Can we print ANALYZE [ FORMAT=JSON] for the other thread?
Ok. Please in the future do not have two branches with similar names like bb-10.8-MDEV-10000 and bb-10.8-mdev-10000. This is confusing
Sergei Petrunia
added a comment - Ok. Please in the future do not have two branches with similar names like bb-10.8- MDEV-10000 and bb-10.8-mdev-10000 . This is confusing
EXPLAIN FOR CONNECTION produces "partitions" and "filtered" columns.
These columns are also part of regular EXPLAIN output (Initially
they weren't and one had to use EXPLAIN EXTENDED to get the "filtered"
column and EXPLAIN PARTITIONS to get the "partitions")
In MariaDB:
EXPLAIN doesn't produce "partitions" or "filtered". One needs to use
EXPLAIN (EXTENDED|PARTITIONS).
The current patch doesn't produce "partitions" or "filtered".
But since we're aiming at MySQL compatibility perhaps we should do that?
Sergei Petrunia
added a comment - One other thing to consider:
In MySQL:
EXPLAIN FOR CONNECTION produces "partitions" and "filtered" columns.
These columns are also part of regular EXPLAIN output (Initially
they weren't and one had to use EXPLAIN EXTENDED to get the "filtered"
column and EXPLAIN PARTITIONS to get the "partitions")
In MariaDB:
EXPLAIN doesn't produce "partitions" or "filtered". One needs to use
EXPLAIN (EXTENDED|PARTITIONS).
The current patch doesn't produce "partitions" or "filtered".
But since we're aiming at MySQL compatibility perhaps we should do that?
Sorry for the confusion, bb-10.8-MDEV-10000 is the actual branch. I removed the other one having lowercase mdev.
Regarding "partitions" and "filtered": is we add these fields only to EXPLAIN FOR CONNECTION output wouldn't it be inconsistent that SHOW EXPLAIN displays one set of columns and EXPLAIN FOR CONNECTION - another one? Doesn't it make sense to add those fields to SHOW EXPLAIN output as well?
Oleg Smirnov
added a comment - - edited Sorry for the confusion, bb-10.8- MDEV-10000 is the actual branch. I removed the other one having lowercase mdev.
Regarding "partitions" and "filtered": is we add these fields only to EXPLAIN FOR CONNECTION output wouldn't it be inconsistent that SHOW EXPLAIN displays one set of columns and EXPLAIN FOR CONNECTION - another one? Doesn't it make sense to add those fields to SHOW EXPLAIN output as well?
Task
Minor
MDEV-28125 Server crashes in Explain_table_access::tag_to_json upon SHOW EXPLAIN FORMAT=JSON
Considerations: