Just rename index in data dictionary and in InnoDB cache when it's possible.
Introduce ALTER_INDEX_RENAME for that purpose so that engines can optimize
such operation.
Unused code between macro MYSQL_RENAME_INDEX was removed.
compare_keys_but_name(): compare index definitions except for index names
Alter_inplace_info::rename_keys:
ha_innobase_inplace_ctx::rename_keys: vector of rename indexes
fill_alter_inplace_info():: fills Alter_inplace_info::rename_keys
Moved rea_create_table() to the sole caller.
Also ha_create_partitioning_metadata(CHF_CREATE_FLAG) does cleanup on
error now.
Part of MDEV-17805 - Remove InnoDB cache for temporary tables.
Do not register intermediate tables created by inplace ALTER TABLE in
THD::temporary_tables.
Regular ALTER TABLE doesn't create .frm for temporary and discoverable
tables anymore. For inplace ALTER TABLE moved .frm creation to
create_table_for_inplace_alter().
Removed open_in_engine argument of create_and_open_tmp_table() and
open_temporary_table(): it became unused after this patch.
Part of MDEV-17805 - Remove InnoDB cache for temporary tables.
This check was introduced in 602a222 and then became redundant in ad1553e,
where we attempt to open a table even for non-copy algorithms.
Added missing test case from 602a222.
Part of MDEV-17805 - Remove InnoDB cache for temporary tables.
CREATE TEMPORARY TABLE locks SE plugin 6 times. 5 of these locks are
released by the end of the statement. And only 1 acquired by
init_from_binary_frm_image() / plugin_lock() remains.
The lock removed in this patch was clearly redundant.
Part of MDEV-17805 - Remove InnoDB cache for temporary tables.
The MDEV-17262 commit 26432e49d37a37d09b862bb49a021e44bdf4789c
was skipped. In Galera 4, the implementation would seem to require
changes to the streaming replication.
In the tests archive.rnd_pos main.profiling, disable_ps_protocol
for SHOW STATUS and SHOW PROFILE commands until MDEV-18974
has been fixed.
attempt to drop BLOB with long index
Restore long table->key_info, So that in the case of unsuccessful table
alter table->key_info should have a correct value. In the case of successful
table alter old table is flushed so that is why we don't see this error in
the case of successful alter.
ALTER TABLE ... ADD FOREIGN KEY may trigger assertion failure when
it has LOCK=EXCLUSIVE clause or concurrent FLUSH TABLES is being
executed.
In both cases being altered table is marked as flushed, which forces
subsequent attempt to open parent table to re-open. Which in turn is
not allowed while transaction is running.
Rather than opening parent table, just take appropriate MDL lock.
Also removed table_already_fk_prelocked() check: MDL itself has much
better methods to handle duplicate locks. E.g. the former won't acquire
MDL_SHARED_NO_WRITE if it already has MDL_SHARED_READ.
when auto-adding a virtual LONG_UNIQUE_HASH_FIELD, fill in
a Virtual_column_info for it, so that fill_alter_inplace_info()
would know we're adding a virtual field (ALTER_ADD_VIRTUAL_COLUMN).
sql_field->key_length was 0 for blob fields when a field was
being added, but Field_blob::character_octet_length() on
subsequent ALTER TABLE's (when the Field object in the old table
already existed). This means mysql_prepare_create_table() couldn't
reliably detect if the keyseg was a prefix.
This patch implements engine independent unique hash index.
Usage:- Unique HASH index can be created automatically for blob/varchar/test column whose key
length > handler->max_key_length()
or it can be explicitly specified.
Automatic Creation:-
Create TABLE t1 (a blob unique);
Explicit Creation:-
Create TABLE t1 (a int , unique(a) using HASH);
Internal KEY_PART Representations:-
Long unique key_info will have 2 representations.
(lets understand this with an example create table t1(a blob, b blob , unique(a, b)); )
1. User Given Representation:- key_info->key_part array will be similar to what user has defined.
So in case of example it will have 2 key_parts (a, b)
2. Storage Engine Representation:- In this case there will be only one key_part and it will point to
HASH_FIELD. This key_part will be always after user defined key_parts.
So:- User Given Representation [a] [b] [hash_key_part]
key_info->key_part ----^
Storage Engine Representation [a] [b] [hash_key_part]
key_info->key_part ------------^
Table->s->key_info will have User Given Representation, While table->key_info will have Storage Engine
Representation.Representation can be changed into each other by calling re/setup_keyinfo_hash function.
Working:-
1. So when user specifies HASH_INDEX or key_length is > handler->max_key_length(), In mysql_prepare_create_table
One extra vfield is added (for each long unique key). And key_info->algorithm is set to HA_KEY_ALG_LONG_HASH.
2. In init_from_binary_frm_image values for hash_keypart is set (like fieldnr , field and flags)
3. In parse_vcol_defs, HASH_FIELD->vcol_info is created. Item_func_hash is used with list of Item_fields,
When Explicit length is given by user then Item_left is used to concatenate Item_field values.
4. In ha_write_row/ha_update_row check_duplicate_long_entry_key is called which will create the hash key from
table->record[0] and then call ha_index_read_map , if we found duplicated hash , we will compare the result
field by field.
After FLUSH PRIVILEGES remember if the connection started under
--skip-grant-tables and keep it all-powerful, not a lowly anonymous.
One could use this connection to reset passwords as needed.
Also fix a crash in SHOW CREATE USER
If we instantly change the size of a fixed-length field
and treat it as kind-of variable-length, then we will need
conversions between old column values and new ones.
I tried adding such a conversion to row_build(), but then I
noticed that more conversions would be needed, because
old values still appeared in a freshly rebuilt secondary index,
causing a mismatch when trying to search with the correct
longer value that was converted in my provisional fix to row_build().
So, we will revert the essential part of
MDEV-15563: Instant ROW_FORMAT=REDUNDANT column extension
(commit 22feb179ae166500ec91feec6246c8154e33f9a2), but not
remove any tests.
This was developed by Aleksey Midenkov based on my design.
In the original InnoDB storage format (that was retroactively named
ROW_FORMAT=REDUNDANT in MySQL 5.0.3), the length of each index field
is stored explicitly.
Because of this, we can and now will allow instant conversion from
VARCHAR to CHAR or VARBINARY to BINARY of equal or greater size,
as well as instant conversion of TINYINT to SMALLINT to MEDIUMINT
to INT to BIGINT (while not changing between signed and unsigned).
Theoretically, we could allow changing from an unsigned integer to
a bigger unsigned integer, as well as changing CHAR to VARCHAR, but
that would require additional metadata and conversions whenever
reading old records.
Field_str::is_equal(), Field_varstring::is_equal(), Field_num::is_equal():
Return the new result IS_EQUAL_PACK_LENGTH_EXT if the table advertises
HA_EXTENDED_TYPES_CONVERSION capability and we are considering the
above-mentioned conversions.
ALTER_COLUMN_EQUAL_PACK_LENGTH_EXT: A new ALTER TABLE flag, similar
to ALTER_COLUMN_EQUAL_PACK_LENGTH but requiring conversions when
reading the data. The Field::is_equal() result IS_EQUAL_PACK_LENGTH_EXT
will map to this flag.
dtype_get_fixed_size_low(): For BINARY, CHAR and integer columns
in ROW_FORMAT=REDUNDANT, return 0 (variable length) from now on.
dtype_get_sql_null_size(): Keep returning the current size for
BINARY, CHAR and integer columns, so that in ROW_FORMAT=REDUNDANT
it will remain possible to update in place between NULL and NOT NULL
values.
btr_index_rec_validate(): Relax a CHECK TABLE length check for
ROW_FORMAT=REDUNDANT tables.
btr_cur_instant_init_low(): No longer trust fixed_len
for ROW_FORMAT=REDUNDANT tables.
We cannot rely on fixed_len anymore because the record can have shorter
length from before instant extension. Note that importing such tablespace
into earlier MariaDB versions produces ER_TABLE_SCHEMA_MISMATCH when
using a .cfg file.
renaming columns in a CHECK constraint during ALTER TABLE
taints the original TABLE and requires m_need_reopen=1.
In this case, though, renaming was redundant, so just don't do it.
remove TABLE_SHARE::error_table_name() and TABLE_SHARE::orig_table_name
(that was allocated in a wrong memroot in this bug).
instead, simply set TABLE_SHARE::table_name correctly.
