varchar to number

CONVERT (varchar (10), field name, conversion format)CONVERT (nvarchar), count_time,121Convert is a date conversion function, typically in the time type (Datetime,smalldatetime) and the string type (Nchar,nvarchar,char,varchar)The 3 parameters of

CONVERT (varchar (10), field name, conversion format)CONVERT (nvarchar), count_time,121Convert is a date conversion function, typically in the time type (Datetime,smalldatetime) and the string type (Nchar,nvarchar,char,varchar)The 3 parameters of

Comparison of data typesChar represents a fixed length, and the longest n-word varchar represents the actual length of the data type, such as: if it is a char type, when you enter a character that is less than the length, then a space is added, but

if the setting in an item is varchar (So, of course, the English isSo what about Chinese?Utf-8 in Chinese is 3 bytesSo, does this varchar (50) have only 16 characters to save? No, this is the case with MySQL, but not after 5.0.MySQL varchar (50)

Summary of varchar types in MySQLToday to do a new project, the need for their own database design, found themselves on the use of varchar is not very familiar with, so review the data summarized if:variations of the 1.varchar typeThe maximum length

Charvarcharvarchar2 differences: 1. the length of CHAR is fixed, while the length of VARCHAR2 can be changed. For example, the storage string "abc", for CHAR (20 ), it indicates that the characters you store will occupy 20 bytes (including 17 null

How to Use substring in oracle Database CONVERT (varchar (12), getdate (), 112), substringgetdate SqlserverI often need to perform some time-type field conversions, but I don't quite remember it. So I collected the following

If a varchar is set in an item (50) Well, that's 50 for English. So what about Chinese? Utf-8 Chinese occupies 3 bytes So, is this varchar (50) Only save 16 characters? MySQL varchar (50) in both Chinese and English, there are 50. MySQL5

Char varchar varchar2 the difference http://blog.csdn.net/honglei_zh/article/details/7172538Difference:1. The length of the char is fixed, and the length of the VARCHAR2 is changeable, for example, storing the string "abc", for Char (20), which

Explore n in char/varchar (n): number of characters or bytes, number of varchar bytes [Problem source] When I display the database table designed, yu asked me, why is the top_info field of your top_info defined type varchar (100) 100, how many