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https://dev.mysql.com/index-page-merge-threshold.html
row *************************** Table: t2 Create Table: CREATE TABLE `t2` ( `id` int(11) DEFAULT NULL, KEY `id_index` (`id`) COMMENT 'MERGE_THRESHOLD=40' ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 Note A MERGE_THRESHOLD value defined at the index level ...If the “page-full” percentage for an index page falls below the MERGE_THRESHOLD value when a row is deleted or when a row is shortened by an UPDATE operation, InnoDB attempts to merge the index page with a neighboring index ...
https://dev.mysql.com/innodb-information-schema-system-tables.html
row *************************** TABLE_ID: 71 NAME: col1 POS: 0 MTYPE: 6 PRTYPE: 1027 LEN: 4 HAS_DEFAULT: 0 DEFAULT_VALUE: NULL *************************** 2. row *************************** TABLE_ID: 71 NAME: col2 POS: 1 MTYPE: 2 PRTYPE: 524542 LEN: ... You can extract metadata about schema objects managed by InnoDB using InnoDB INFORMATION_SCHEMA ...
https://dev.mysql.com/innodb-troubleshooting-datadict.html
Information about table definitions is stored in the InnoDB data dictionary. If you move data files around, dictionary data can become inconsistent. If a data dictionary corruption or consistency issue prevents you from starting InnoDB, see Section ...
https://dev.mysql.com/insert.html
Warnings can occur under any of the following conditions: Inserting NULL into a column that has been declared NOT NULL. (For a single-row INSERT, no warning occurs when NULL is inserted into a NOT NULL column. INSERT [LOW_PRIORITY | DELAYED | ...
https://dev.mysql.com/invisible-indexes.html
A table with no explicit primary key may still have an effective implicit primary key if it has any UNIQUE indexes on NOT NULL columns. MySQL supports invisible indexes; that is, indexes that are not used by the optimizer. The feature applies to ...
https://dev.mysql.com/locking-functions.html
Returns 1 if the lock was obtained successfully, 0 if the attempt timed out (for example, because another client has previously locked the name), or NULL if an error occurred (such as running out of memory or the thread was killed with mysqladmin ...
https://dev.mysql.com/mysql-cluster-ndbinfo-operations-per-fragment.html
The operations_per_fragment table provides information about the operations performed on individual fragments and fragment replicas, as well as about some of the results from these operations. The following table provides information about the ...
https://dev.mysql.com/mysql-cluster-options-variables.html
row *************************** id: 1 select_type: SIMPLE table: d type: ALL possible_keys: PRIMARY key: NULL key_len: NULL ref: NULL rows: 9 Extra: Parent of 4 pushed join@1 *************************** 2. ndb_slave_conflict_role can take any one of ... This section provides information about MySQL server options, server and status variables that are specific to NDB ...
https://dev.mysql.com/mysql-cluster-privilege-distribution.html
NDB 8.0.18 introduces a new mechanism for sharing and synchronizing users, roles, and privileges between SQL nodes connected to an NDB Cluster. NDB_STORED_USER is printed in the output of SHOW GRANTS as with any other privilege. A statement ...
https://dev.mysql.com/mysql-library-init.html
#include <mysql.h> #include <stdlib.h> int main(void) { if (mysql_library_init(0, NULL, NULL)) { fprintf(stderr, "could not initialize MySQL client library\n"); exit(1); } /* Use any MySQL API functions here */ mysql_library_end(); return ... int ...
Document created the 26/06/2006, last modified the 26/10/2018
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