Question

if I started mysqldump on a database, and then created a new table with new data, will this table be dumped? what’s the concurrency behavior here?

Answer 1

Well, that is not sure, from Mysql Manual:

–single-transaction

This option sends a START TRANSACTION
SQL statement to the server before
dumping data. It is useful only with
transactional tables such as InnoDB
and BDB, because then it dumps the
consistent state of the database at
the time when BEGIN was issued without
blocking any applications.

When using this option, you should
keep in mind that only InnoDB tables
are dumped in a consistent state. For
example, any MyISAM or MEMORY tables
dumped while using this option may
still change state.

While a –single-transaction dump is
in process, to ensure a valid dump
file (correct table contents and
binary log coordinates), no other
connection should use the following
statements: ALTER TABLE, CREATE TABLE,
DROP TABLE, RENAME TABLE, TRUNCATE
TABLE. A consistent read is not
isolated from those statements, so use
of them on a table to be dumped can
cause the SELECT that is performed by
mysqldump to retrieve the table
contents to obtain incorrect contents
or fail.

The –single-transaction option and
the –lock-tables option are mutually
exclusive because LOCK TABLES causes
any pending transactions to be
committed implicitly.

This option is not supported for MySQL
Cluster tables; the results cannot be
guaranteed to be consistent due to the
fact that the NDBCLUSTER storage
engine supports only the
READ_COMMITTED transaction isolation
level. You should always use NDB
backup and restore instead.

To dump large tables, you should
combine the –single-transaction
option with –quick.

If you want to backup/move your live DB, you should consider MySQL replication