rem0types.h

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This program is free software; you can redistribute it and/or modify it under
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FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

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/********************************************************************/
#ifndef rem0types_h
#define rem0types_h

/* We define the physical record simply as an array of bytes */
typedef byte    rec_t;

/* Maximum values for various fields (for non-blob tuples) */
#define REC_MAX_N_FIELDS        (1024 - 1)
#define REC_MAX_HEAP_NO         (2 * 8192 - 1)
#define REC_MAX_N_OWNED         (16 - 1)

/* Maximum number of user defined fields/columns. The reserved columns
are the ones InnoDB adds internally: DB_ROW_ID, DB_TRX_ID, DB_ROLL_PTR.
We need "* 2" because mlog_parse_index() creates a dummy table object
possibly, with some of the system columns in it, and then adds the 3
system columns (again) using dict_table_add_system_columns(). The problem
is that mlog_parse_index() cannot recognize the system columns by
just having n_fields, n_uniq and the lengths of the columns. */
#define REC_MAX_N_USER_FIELDS   (REC_MAX_N_FIELDS - DATA_N_SYS_COLS * 2)

/* REC_ANTELOPE_MAX_INDEX_COL_LEN is measured in bytes and is the maximum
indexed field length (or indexed prefix length) for indexes on tables of
ROW_FORMAT=REDUNDANT and ROW_FORMAT=COMPACT format.
Before we support UTF-8 encodings with mbmaxlen = 4, a UTF-8 character
may take at most 3 bytes.  So the limit was set to 3*256, so that one
can create a column prefix index on 256 characters of a TEXT or VARCHAR
column also in the UTF-8 charset.
This constant MUST NOT BE CHANGED, or the compatibility of InnoDB data
files would be at risk! */
#define REC_ANTELOPE_MAX_INDEX_COL_LEN          768

#define REC_VERSION_56_MAX_INDEX_COL_LEN        3072

enum rec_format_enum {
        REC_FORMAT_REDUNDANT    = 0,    
        REC_FORMAT_COMPACT      = 1,    
        REC_FORMAT_COMPRESSED   = 2,    
        REC_FORMAT_DYNAMIC      = 3     
};
typedef enum rec_format_enum rec_format_t;

#endif