Hi Oleg,

commit 53d4d2852463714678b6e753ecffc1ecdde13891 Author: Oleg Smirnov Date: Thu Jan 13 19:24:22 2022 +0300

MDEV-10000 Add support for FORMAT=JSON

Makes possible calls to SHOW EXPLAIN and EXPLAIN FOR CONNECTION providing output in JSON format: - SHOW EXPLAIN FORMAT=JSON FOR $con - EXPLAIN FORMAT=JSON FOR CONNECTION $con

The patch is mostly ok. I have a few cosmetic comments. Please follow the coding style and make sure the lines are no longer than 80 chars.

diff --git a/sql/sql_show.h b/sql/sql_show.h index 3d7a4d1146c..8c8ae416699 100644 --- a/sql/sql_show.h +++ b/sql/sql_show.h @@ -164,6 +164,9 @@ class Show_explain_request : public Apc_target::Apc_call THD *target_thd; /* thd that we're running SHOW EXPLAIN for */ THD *request_thd; /* thd that run SHOW EXPLAIN command */

+ bool is_json_format= false; /* set to TRUE if you need the result in JSON + format, FALSE - in traditional tabular */ + Multi-line comments must precede the variable:

/* Comment here... */ bool is_json_format;

/* If true, there was some error when producing EXPLAIN output. */ bool failed_to_produce;

diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy index 74757970411..a7188762cbd 100644 --- a/sql/sql_yacc.yy +++ b/sql/sql_yacc.yy @@ -13945,12 +13945,13 @@ show_param: Lex->spname= $3; Lex->sql_command = SQLCOM_SHOW_CREATE_EVENT; } - | describe_command FOR_SYM expr + | describe_command opt_format_json FOR_SYM expr { Lex->sql_command= SQLCOM_SHOW_EXPLAIN; - if (unlikely(prepare_schema_table(thd, Lex, 0, SCH_EXPLAIN))) + if (unlikely(prepare_schema_table(thd, Lex, 0, + Lex->explain_json ? SCH_EXPLAIN_JSON : SCH_EXPLAIN_TABULAR))) MYSQL_YYABORT; - add_value_to_list(thd, $3); + add_value_to_list(thd, $4); } | IDENT_sys remember_tok_start wild_and_where { @@ -14123,12 +14124,18 @@ opt_describe_column: ;

Please fix identation of this rule to match of identation of others. Please also add a comment about the alternative syntax, both here and in the SHOW EXPLAIN rule.

explain_for_connection: - describe_command FOR_SYM CONNECTION_SYM expr + describe_command opt_format_json FOR_SYM CONNECTION_SYM expr { + Lex->wild=0; + Lex->ident= null_clex_str; + mysql_init_select(Lex); + Lex->current_select->parsing_place= SELECT_LIST; + Lex->create_info.init(); Lex->sql_command= SQLCOM_SHOW_EXPLAIN; - if (unlikely(prepare_schema_table(thd, Lex, 0, SCH_EXPLAIN))) + if (unlikely(prepare_schema_table(thd, Lex, 0, + Lex->explain_json ? SCH_EXPLAIN_JSON : SCH_EXPLAIN_TABULAR))) MYSQL_YYABORT; - add_value_to_list(thd, $4); + add_value_to_list(thd, $5); } ;

BR Sergei -- Sergei Petrunia, Software Developer MariaDB Corporation | Skype: sergefp | Blog: http://petrunia.net