data0type.cc File Reference

Data types. More...

#include "data0type.h"
#include "rem0rec.h"
#include <sys/types.h>
#include "ha_prototypes.h"

Functions
ulint	dtype_get_at_most_n_mbchars (ulint prtype, ulint mbminmaxlen, ulint prefix_len, ulint data_len, const char *str)
	Determine how many bytes the first n characters of the given string occupy. More...
bool	dtype_is_string_type (ulint mtype)
	Checks if a data main type is a string type. More...
bool	dtype_is_binary_string_type (ulint mtype, ulint prtype)
	Checks if a type is a binary string type. More...
bool	dtype_is_non_binary_string_type (ulint mtype, ulint prtype)
	Checks if a type is a non-binary string type. More...
ulint	dtype_form_prtype (ulint old_prtype, ulint charset_coll)
	Forms a precise type from the < 4.1.2 format precise type plus the charset-collation code. More...
bool	dtype_validate (const dtype_t *type)
	Validates a data type structure. More...
void	dtype_print (const dtype_t *type)
	Print a data type structure. More...

Variables
ulint	data_mysql_default_charset_coll

Detailed Description

Data types.

Created 1/16/1996 Heikki Tuuri

Function Documentation

dtype_form_prtype()

ulint dtype_form_prtype	(	ulint	old_prtype,
		ulint	charset_coll
	)

Forms a precise type from the < 4.1.2 format precise type plus the charset-collation code.

Returns

precise type, including the charset-collation code

Parameters

old_prtype	in: the MySQL type code and the flags DATA_BINARY_TYPE etc.
charset_coll	in: MySQL charset-collation code

dtype_get_at_most_n_mbchars()

ulint dtype_get_at_most_n_mbchars	(	ulint	prtype,
		ulint	mbminmaxlen,
		ulint	prefix_len,
		ulint	data_len,
		const char *	str
	)

Determine how many bytes the first n characters of the given string occupy.

If the string is shorter than n characters, returns the number of bytes the characters in the string occupy.

Returns

length of the prefix, in bytes

Parameters

prtype	in: precise type
mbminmaxlen	in: minimum and maximum length of a multi-byte character
prefix_len	in: length of the requested prefix, in characters, multiplied by dtype_get_mbmaxlen(dtype)
data_len	in: length of str (in bytes)
str	in: the string whose prefix length is being determined

dtype_is_binary_string_type()

bool dtype_is_binary_string_type	(	ulint	mtype,
		ulint	prtype
	)

Checks if a type is a binary string type.

Note that for tables created with < 4.0.14, we do not know if a DATA_BLOB column is a BLOB or a TEXT column. For those DATA_BLOB columns this function currently returns false.

Returns

true if binary string type

Parameters

mtype	in: main data type
prtype	in: precise type

dtype_is_non_binary_string_type()

bool dtype_is_non_binary_string_type	(	ulint	mtype,
		ulint	prtype
	)

Checks if a type is a non-binary string type.

That is, dtype_is_string_type is true and dtype_is_binary_string_type is false. Note that for tables created with < 4.0.14, we do not know if a DATA_BLOB column is a BLOB or a TEXT column. For those DATA_BLOB columns this function currently returns true.

Returns

true if non-binary string type

Parameters

mtype	in: main data type
prtype	in: precise type

dtype_is_string_type()

bool dtype_is_string_type

(

ulint

mtype

)

Checks if a data main type is a string type.

Also a BLOB is considered a string type.

Returns

true if string type

Parameters

mtype

in: InnoDB main data type code: DATA_CHAR, ...

dtype_print()

void dtype_print

(

const dtype_t *

type

)

Print a data type structure.

Parameters

[in]

type

data type

dtype_validate()

bool dtype_validate

(

const dtype_t *

type

)

Validates a data type structure.

Returns

true if ok

Parameters

type	in: type struct to validate

Variable Documentation

data_mysql_default_charset_coll

ulint data_mysql_default_charset_coll