Each database, table, column, index, trigger, or view has a name by which it is identified
and almost always the name is supplied by the developer.The rules governing how a
valid identifier is formed in SQLite are set out in the next few sections.
Valid Characters
An identifier name must begin with a letter or the underscore character, which may be
followed by a number of alphanumeric characters or underscores. No other characters
may be present.
These identifier names are valid:
mytable
my_field
xyz123
a
my_field
xyz123
a
However, the following are not valid identifiers:
my table
my-field
123xyz
my-field
123xyz
Name Length
SQLite does not have a fixed upper limit on the length of an identifier name, so any
name that you find manageable to work with is suitable.
Reserved Keywords
Care must be taken when using SQLite keywords as identifier names. As a general rule
of thumb you should try to avoid using any keywords from the SQL language as identifiers,
although if you really want to do so, they can be used providing they are enclosed
in square brackets.
For instance the following statement will work just fine, but this should not be mimicked
on a real database for the sake of your own sanity.
sqlite> CREATE TABLE [TABLE] (
...> [SELECT],
...> [INTEGER] INTEGER,
...> [FROM],
...> [TABLE]
...> );
Case Sensitivity
For the most part, case sensitivity in SQLite is off.Table names and column names can
be typed in uppercase, lowercase, or mixed case, and different capitalizations of the same
database object name can be used interchangeably.
SQL commands are always shown in this book with the keywords in uppercase for
clarity; however, this is not a requirement.
Note
The CREATE TABLE, CREATE VIEW, CREATE INDEX, and CREATE TRIGGER statements all store
the exact way in which they were typed to the database so that the command used to create a database
object can be retrieved by querying the sqlite_master table. Therefore it is always a good idea to format
your CREATE statements clearly, so they can be referred to easily in the future.
the exact way in which they were typed to the database so that the command used to create a database
object can be retrieved by querying the sqlite_master table. Therefore it is always a good idea to format
your CREATE statements clearly, so they can be referred to easily in the future.
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