Active transactions must not switch table or index definitions on the fly,
for several reasons, including the following:
* copied indexes do not carry any history or locking information;
that is, rollbacks, read views, and record locking would be broken
* huge potential for race conditions, inconsistent reads and writes,
loss of data, and corruption
Instead of trying to track down if the table was changed during a transaction,
acquire appropriate locks that protect the creation and dropping of indexes.
innodb-index.test: Test the locking of CREATE INDEX and DROP INDEX. Test
that consistent reads work across dropped indexes.
lock_rec_insert_check_and_lock(): Relax the lock_table_has() assertion.
When inserting a record into an index, the table must be at least IX-locked.
However, when an index is being created, an IS-lock on the table is
sufficient.
row_merge_lock_table(): Add the parameter enum lock_mode mode, which must
be LOCK_X or LOCK_S.
row_merge_drop_table(): Assert that n_mysql_handles_opened == 0.
Unconditionally drop the table.
ha_innobase::add_index(): Acquire an X or S lock on the table, as appropriate.
After acquiring an X lock, assert that n_mysql_handles_opened == 1.
Remove the comments about dropping tables in the background.
ha_innobase::final_drop_index(): Acquire an X lock on the table.
dict_table_t: Remove version_number, to_be_dropped, and prebuilts.
ins_node_t: Remove table_version_number.
enum lock_mode: Move the definition from lock0lock.h to lock0types.h.
ROW_PREBUILT_OBSOLETE, row_update_prebuilt(), row_prebuilt_table_obsolete():
Remove.
row_prebuilt_t: Remove the declaration from row0types.h.
row_drop_table_for_mysql_no_commit(): Always print a warning if a table
was added to the background drop queue.
innobase_rec_to_mysql(): New function, for converting an InnoDB clustered
index record to MySQL table->record[0]. TODO: convert integer fields.
Currently, integer fields are in big-endian byte order instead of
host byte order, and signed integer fields are offset by 0x80000000.
innobase_rec_reset(): New function, for resetting table->record[0].
row_merge_build_indexes(): Add the parameter TABLE* table (the MySQL table
handle) for reporting duplicate key values.
dtuple_from_fields(): New function, to convert an array of dfield_t* to
dtuple_t.
dtuple_get_n_ext(): New function, to compute the number of externally stored
fields.
row_merge_dup_t: Structure for counting and reporting duplicate records.
row_merge_dup_report(): Function for counting and reporting duplicate records.
row_merge_tuple_cmp(), row_merge_tuple_sort(): Replace the ulint* n_dup
parameter with row_merge_dup_t* dup.
row_merge_buf_sort(): Add the parameter row_merge_dup_t* dup, which is
NULL when sorting a non-unique index.
row_merge_buf_write(), row_merge_heap_create(), row_merge_read_rec(),
row_merge_cmp(), row_merge_read_clustered_index(), row_merge_blocks(),
row_merge(), row_merge_sort(): Add const qualifiers.
row_merge_read_clustered_index(): Use a common error handling branch err_exit.
Invoke row_merge_buf_sort() differently on unique indexes.
row_merge_blocks(): note TODO: We could invoke innobase_rec_to_mysql()
to report duplicate key values when creating a clustered index.
This will be needed for fixing Bug #22496.
REC_MAX_INDEX_COL_LEN: New constant, copied from DICT_MAX_INDEX_COL_LEN.
row_ext_create(), row_ext_lookup(), row_ext_lookup_low(): New functions.
