I have a problem: when I create a table in MySQL, I'm asked to fill up some information about each column.
| Name | Type | Value | 2nd Value | Attributes | Null | Default | what do they are??
name, default it's ok, I know them. But the others??? Type.
for example, I have to choose between :-
VARCHAR, TINYINT, SMALLINT, MEDIUMINT, INT, INTEGER, BIGINT, FLOAT, DOUBLE, REAL, DECIMAL, NUMERIC, DATE, TIME, DATETIME, TIMESTAMP, YEAR, CHAR, VARCHAR, TINYBLOB, TINYTEXT, BLOB, TEXT and others....
Or also in Attibutes:
"NONE, UNSIGNED, BINARY, ZEROFILL"
May some one explain that? or, is there a link that you know I can find explanation to that?
I'll just explain each one to the best of my ability - Name - the name of the column, pretty self-explanatory (e.g., "username")Type - you got it, one of those data types (e.g., VARCHAR(20) = 20 char string)Value - the information stored in that column (e.g., "alexviii")2nd Value - I've never used it, I guess it's just another value, thoughAttributes - not sure, might be something like primary key, etc.Null - whether or not it can be null (an optional field would be able to be null)Default - the default value, usually null if it can be null
While making a table you need to give it its name.
How would you query it otherwise ?
Also the type means what type of data.
Numeric or Alphanumeric.
Numeric can store only numbers while Alphanumeric can store both but it can be used in calculations as it is regarded as a string.
Also all Alphanumeric are having default value as NULL unless you give it some value as defualt.
All numeric ones have 0 as default unless you give a default number.
A good tutorial site:
Hope it helps
Name -> the name of the column.Type -> Type of the column (Varchar for alphanumeric, char same, INT for numeric, text for large string, BLOB for binary data like sounds or images)Value -> the length of the column in integer (e.g: 5 for integer means INT(5) so this column can countain like 54321Attribut -> I never fill itNull -> wheter this column can be empty or not.Default -> the default value for this columnAlsoAUTO_INCREMENT -> the value of this column always increase by 1 if you add new record.PRIMARY_KEY -> no duplicate value for this columnUNIQUE -> no duplicate value
10x guys, Let's Say I have to make a table like this: Id = Autoincremet id username password realname = the name of the applicant realsurname= his surname country = chosen from a list of countrys in the form e-mail url = web site avatar = which is uploaded in the form rank = auotomaticaly is always 1 (than from the admin it can be changed to 2 or 3 etc..) date = when he register Thoese are the information that I need to store for all client. How do I create a querry for that?? 10x