Since we asked for four fields, we
get four rows, each row referring to information specific to one field:
??? ??? ??? ???
Chapter 4
[ 69 ]
The two following images are enlargements of the left and right sides for this panel:
On pre-4.1 MySQL versions, the Collation and Comments columns
might not be shown at this point. Please refer to Chapter 17, Character Sets
and Collations, for collation issues, and to Chapter 11, Relational System, for
column commenting.
The MySQL documentation explains valid characters for table and field names
(if we search for Legal names). This may vary depending on the MySQL version.
Usually, any character that is allowed in a file name (except the dot and the slash) is
acceptable in a table name, and the length of the name must not exceed 64 characters.
The 64-character limit exists for field names as well, but we can use any character.
First Steps
[ 70 ]
We enter our field names under the Field column. Each field has a type, the
VARCHAR type (variable character) being the default since it is the most
commonly used.
The VARCHAR type is widely used when the field content is alphanumeric, because
the contents will occupy only the space needed for it. This type requires a maximum
length, which we specify. If we forget to do so, a small pop-up message reminds us
later when we save.
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