Hi!
On Jul 31, Alexander Nozdrin wrote:
> ChangeSet@stripped, 2007-07-31 20:02:39+04:00, anozdrin@ibm. +1 -0
> Fix for BUG#30123: mysqldump is unable to work with old servers.
>
> New server (as of 5.1.21) provides new features:
> - SHOW CREATE TRIGGER;
> - character set information for SHOW TRIGGERS and SHOW CREATE
> EVENT | FUNCTION | PROCEDURE statements.
> Mysqldump uses these features to generate proper dump.
>
> The bug happened when new mysqldump was used to dump older servers.
> The problem was that 5.1.21 new features are not available, so
> mysqldump exited with error code or just crashed.
>
> The fix is to detect if mysqldump has ben run against older server
> and don't use new 5.1.21 functionality in this case. Certainly,
> the dump generated for the older server suffers from the character
> set problems fixed by BUG#16291 and the like.
>
> client/mysqldump.c@stripped, 2007-07-31 20:02:28+04:00, anozdrin@ibm. +374 -177
> Don't use new server features if they are not available.
Thanks.
Please, see my comments below
> diff -Nrup a/client/mysqldump.c b/client/mysqldump.c
> --- a/client/mysqldump.c 2007-07-27 22:20:27 +04:00
> +++ b/client/mysqldump.c 2007-07-31 20:02:28 +04:00
> @@ -1227,6 +1227,126 @@ static int switch_character_set_results(
> return mysql_real_query(mysql, query_buffer, query_length);
> }
>
> +/**
> + Cover DEFINER-clause for CREATE TRIGGER statement in version-specific
> + comments.
Not a very good comment. What does it mean "cover definer clause" ?
I don't understand what this function is suppose to do.
> + TODO: this is definitely a BAD IDEA to parse SHOW CREATE output.
> + However, we can not use INFORMATION_SCHEMA instead:
> + 1. INFORMATION_SCHEMA provides data in UTF8, but here we need data in
> + the original character set;
> + 2. INFORMATION_SCHEMA does not provide information about routine
> + parameters now.
> +
> + @param[in] trigger_def_str CREATE TRIGGER statement string.
> + @param[in] trigger_def_length length of the trigger_def_str.
> +
> + @return pointer to the new allocated query string.
> +*/
> +
> +static char *cover_definer_clause_in_trigger(const char *trigger_def_str,
> + uint trigger_def_length)
...
> @@ -1766,16 +1886,36 @@ static uint dump_events_for_db(char *db)
...
> + }
> + else
> + {
> + /*
> + mysqldump is being run against the server, that does not
> + provide character set information in SHOW CREATE
> + statements.
> +
> + NOTE: the dump may be incorrect, since character set
> + information is required in order to restore event properly.
> + */
> +
> + fprintf(sql_file,
> + "--\n"
> + "-- WARNING: old server version. "
> + "The following dump may be incomplete.\n"
> + "--\n");
Are you sure it's a good idea to add this warning before every
procedure, every function, every trigger, and every event ?
> + }
>
> switch_sql_mode(sql_file, delimiter, row[1]);
>
> @@ -2660,18 +2778,109 @@ continue_xml:
...
> +static int dump_triggers_for_table(char *table_name, char *db_name)
> +{
> + FILE *sql_file= md_result_file;
> + char name_buff[NAME_LEN*4+3];
> + char query_buff[QUERY_LENGTH];
> + uint old_opt_compatible_mode= opt_compatible_mode;
> + MYSQL_RES *show_triggers_rs;
> + MYSQL_ROW row;
> +
> + char db_cl_name[MY_CS_NAME_SIZE];
> +
> + DBUG_ENTER("dump_triggers_for_table");
> + DBUG_PRINT("enter", ("db: %s, table_name: %s", db_name, table_name));
> +
> + /* Do not use ANSI_QUOTES on triggers in dump */
> + opt_compatible_mode&= ~MASK_ANSI_QUOTES;
> +
> + /* Get database collation. */
> +
> + if (fetch_db_collation(db_name, db_cl_name, sizeof (db_cl_name)))
> + DBUG_RETURN(TRUE);
> +
> + if (switch_character_set_results(mysql, "binary"))
> + DBUG_RETURN(TRUE);
In the old code I don't see switch to binary charset.
Why it's here ? It doesn't look like this change is related to "old
mysqld servers".
> + /* Get list of triggers. */
> +
> + my_snprintf(query_buff, sizeof(query_buff),
> + "SHOW TRIGGERS LIKE %s",
> + quote_for_like(table_name, name_buff));
> +
> + if (mysql_query_with_error_report(mysql, &show_triggers_rs, query_buff))
> + DBUG_RETURN(TRUE);
> +
> + if (mysql_num_rows(show_triggers_rs))
> + fprintf(sql_file, "\n");
> +
> + /* Dump triggers. */
Regards / Mit vielen Grüssen,
Sergei
--
__ ___ ___ ____ __
/ |/ /_ __/ __/ __ \/ / Sergei Golubchik <serg@stripped>
/ /|_/ / // /\ \/ /_/ / /__ Principal Software Developer
/_/ /_/\_, /___/\___\_\___/ MySQL GmbH, Radlkoferstr. 2, D-81373 München
<___/ Geschäftsführer: Kaj Arnö - HRB
München 162140
