Mysql的varchar类型
自从认识mysql的那天起就知道varchar的长度限制为255，不过现在这种情况已经改变了：
Values in VARCHAR columns are variable-length strings. The length can be specified as a value from 0 to 65,535. The effective maximum length of a VARCHAR is subject to the maximum row size (65,535 bytes, which is shared among all columns) and the character set used.
In contrast to CHAR, VARCHAR values are stored as a one-byte or two-byte length prefix plus data. The length prefix indicates the number of bytes in the value. A column uses one length byte if values require no more than 255 bytes, two length bytes if values may require more than 255 bytes.
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The following table illustrates the differences between CHAR and VARCHAR by showing the result of storing various string values into CHAR(4) and VARCHAR(4) columns (assuming that the column uses a single-byte character set such as latin1).
Value
CHAR(4)
Storage Required
VARCHAR(4)
Storage Required
''
' '
4 bytes
''
1 byte
'ab'
'ab '
4 bytes
'ab'
3 bytes
'abcd'
'abcd'
4 bytes
'abcd'
5 bytes
'abcdefgh'
'abcd'
4 bytes
'abcd'
5 bytes
（http://dev.mysql.com/doc/refman/5.1/en/char.html）
以后基本可以不使用text字段了。。。。。。
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Oracle Data Type
BIGINT
NUMBER(19, 0)
BIT
RAW
BLOB
BLOB, RAW
CHAR
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DATE
DATE
DATETIME
DATE
DECIMAL
FLOAT (24)
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FLOAT (24)
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FLOAT
FLOAT
INT
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INTEGER
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1. mysql -u root -pvmwaremysql>us ......
#include <winsock2.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <mysql.h>
#pragma comment(lib,"libmysql")
int _tmain(int argc, _TCHAR* argv[])
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MYSQL* mysql;
MYSQL_RES* results;
MYSQL_ROW record;
mysql = mysql_init(NULL);
if(! ......
