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https://dev.mysql.com/innodb-compression-internals.html
The compression of B-tree nodes (of both clustered and secondary indexes) is handled differently from compression of overflow pages used to store long VARCHAR, BLOB, or TEXT columns, as explained in the following sections. Compressing BLOB, VARCHAR, ... This section describes some internal implementation details about compression for InnoDB ...
https://dev.mysql.com/memory-use.html
For each concurrent thread, a table structure, column structures for each column, and a buffer of size 3 * N are allocated (where N is the maximum row length, not counting BLOB columns). A BLOB column requires five to eight bytes plus the length of ... MySQL allocates buffers and caches to improve performance of database ...
https://dev.mysql.com/mysql-cluster-programs-ndb-restore.html
All NDB 8.0 releases --rewrite-database=olddb,newdb Restores to a database with a different name than the original All NDB 8.0 releases --skip-broken-objects Causes missing blob tables in the backup file to be ignored. When converting between ...
https://dev.mysql.com/innodb-buffer-page-lru-table.html
The INNODB_BUFFER_PAGE_LRU table provides information about the pages in the InnoDB buffer pool; in particular, how they are ordered in the LRU list that determines which pages to evict from the buffer pool when it becomes full. The ...
https://dev.mysql.com/innodb-buffer-page-table.html
The INNODB_BUFFER_PAGE table provides information about each page in the InnoDB buffer pool. For related usage information and examples, see Section 15.14.5, “InnoDB INFORMATION_SCHEMA Buffer Pool Tables”. Do not query this table on a ...
https://dev.mysql.com/storage-requirements.html
This figure excludes BLOB or TEXT columns, which contribute only 9 to 12 bytes toward this size. For BLOB and TEXT data, the information is stored internally in a different area of memory than the row buffer. VARCHAR, VARBINARY, and the BLOB and ...
https://dev.mysql.com/mysql-cluster-ndbinfo-operations-per-fragment.html
This currently has the following formats: Base table: - DbName/def/TblName BLOB table: - DbName/def/NDB$BLOB_BaseTblId_ColNo Ordered index: - sys/def/BaseTblId/IndexName Unique index: - sys/def/BaseTblId/IndexName$unique The $unique suffix shown for ... 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 ...
https://dev.mysql.com/c-api-data-structures.html
(The BLOB_FLAG and TIMESTAMP_FLAG flags are unneeded.) ENUM and SET values are returned as strings. This enables you to distinguish BINARY from CHAR, VARBINARY from VARCHAR, and the BLOB types from the TEXT types. This section describes C API data ...
https://dev.mysql.com/string-functions.html
mysql> UPDATE t SET blob_col=LOAD_FILE('/tmp/picture') WHERE id=1; LOCATE(substr,str), LOCATE(substr,str,pos) The first syntax returns the position of the first occurrence of substring substr in string str. mysql> SELECT LOWER('QUADRATICALLY'); -> ...For functions that operate on string positions, the first position is numbered ...
https://dev.mysql.com/innodb-restrictions.html
ERROR 1070 (42000): Too many key parts specified; max 16 parts allowed The maximum row length, except for variable-length columns (VARBINARY, VARCHAR, BLOB and TEXT), is slightly less than half of a page for 4KB, 8KB, 16KB, and 32KB page sizes.
Document created the 26/06/2006, last modified the 26/10/2018
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