tokenreq.html

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</b></blockquote><a name="H41050"></a>
<p>
  An unrecognized token generates an immediate error and aborts the parse.
</p><blockquote><b>H41050:</b>
  When the tokenizer encounters text that is not a valid token, it shall
  cause an error to be returned to the application.
</b></blockquote>
<h3>Whitespace tokens</h3>
<a name="H41100"></a>
<p>
  Whitespace has the usual definition.
</p><blockquote><b>H41100:</b>
  SQLite shall recognize a sequence of one or more WHITESPACE characters
  as a WHITESPACE token.
</b></blockquote><a name="H41110"></a>
<p>
  An SQL comment is "--" through the end of line and is understood as
  whitespace.
</p><blockquote><b>H41110:</b>
  SQLite shall recognize as a WHITESPACE token the two-character sequence "--" 
  (u002d, u002d) followed by any sequence of non-zero characters up through and
  including the first u000a character or until end of input.
</b></blockquote><a name="H41120"></a>
<p>
  A C-style comment "/*...*/" is also recognized as white-space.
</p><blockquote><b>H41120:</b>
  SQLite shall recognize as a WHITESPACE token the two-character sequence "/*"
  (u002f, u002a) followed by any sequence of zero or more 
  non-zero characters through with the first "*/" (u002a, u002f) sequence or 
  until end of input.
</b></blockquote>
<h3>Identifier tokens</h3>
<a name="H41130"></a>
<p>
  Identifiers follow the usual rules with the exception that SQLite
  allows the dollar-sign symbol in the interior of an identifier.
  The dollar-sign is for compatibility with Microsoft SQL-Server
  and is not part of the SQL standard.
</p><blockquote><b>H41130:</b>
  SQLite shall recognize as an ID token 
  any sequence of characters that begins with
  an ALPHABETIC character and continue with zero or more
  ALPHANUMERIC characters and/or "$" (u0024) characters and which is
  not a keyword token.
</b></blockquote><a name="H41140"></a>
<p>
  Identifiers can be arbitrary character strings within square brackets.
  This feature is also for compatibility with Microsoft SQL-Server
  and not a part of the SQL standard.
</p><blockquote><b>H41140:</b>
  SQLite shall recognize as an ID token
  any sequence of non-zero characters that begins with "&#91;" (u005b) and
  continuing through the first "&#93;" (u005d) character.
</b></blockquote><a name="H41150"></a>
<p>
  The standard way of quoting SQL identifiers is to use double-quotes.
</p><blockquote><b>H41150:</b>
  SQLite shall recognize as an ID token
  any sequence of characters
  that begins with a double-quote (u0022), is followed by zero or
  more non-zero characters and/or pairs of double-quotes (u0022)
  and terminates with a double-quote (u0022) that
  is not part of a pair.
</b></blockquote><a name="H41160"></a>
<p>
  MySQL allows identifiers to be quoted using the grave accent character.
  SQLite supports this for interoperability.
</p><blockquote><b>H41160:</b>
  SQLite shall recognize as an ID token
  any sequence of characters
  that begins with a grave accent (u0060), is followed by zero or
  more non-zero characters and/or pairs ofgrave accents (u0060)
  and terminates with a grave accent (u0022) that
  is not part of a pair.
</b></blockquote>
<h3>Literals</h3>
<a name="H41200"></a>
<p>
  This is the usual definition of string literals for SQL.
  SQL uses the classic Pascal string literal format.
</p><blockquote><b>H41200:</b>
  SQLite shall recognize as a STRING token a sequence of characters
  that begins with a single-quote (u0027), is followed by zero or
  more non-zero characters and/or pairs of single-quotes (u0027)
  and terminates with a single-quote (u0027) that
  is not part of a pair.
</b></blockquote><a name="H41210"></a>
<p>
  Blob literals are similar to string literals except that they
  begin with a single "X" character and contain hexadecimal data.
</p><blockquote><b>H41210:</b>
  SQLite shall recognize as a BLOB token an upper or lower-case "X"
  (u0058 or u0078) followed by a single-quote (u0027) followed by
  a number of HEXADECIMAL character that is a multiple of two and
  terminated by a single-quote (u0027).
</b></blockquote><a name="H41220"></a>
<p>
  Integer literals are a string of digits.  The plus or minus sign
  that might optionally preceed an integer is not part of the integer
  token.
</p><blockquote><b>H41220:</b>
  SQLite shall recognize as an INTEGER token any squence of
  one or more NUMERIC characters.
</b></blockquote><a name="H41230"></a>
<p>
  An "exponentiation suffix" is defined to be an upper or lower
  case "E" (u0045 or u0065) followed by one or more NUMERIC
  characters.  The "E" and the NUMERIC characters may optionally
  be separated by a plus-sign (u002b) or a minus-sign (u002d).
  An exponentiation suffix is part of the definition of a FLOAT
  token:
</p><blockquote><b>H41230:</b>
  SQLite shall recognize as a FLOAT token a sequence of one
  or more NUMERIC characters together with zero or one period
  (u002e) and followed by an exponentiation suffix.
</b></blockquote><a name="H41240"></a>
<blockquote><b>H41240:</b>
  SQLite shall recognize as a FLOAT token a sequence of one
  or more NUMERIC characters that includes exactly one period
  (u002e) character.
</b></blockquote>
<h3>Variables</h3>
<a name="H40310"></a>
<p>
  Variables are used as placeholders in SQL statements for constant
  values that are to be bound at start-time.
</p><blockquote><b>H40310:</b>
  SQLite shall recognize as a VARIABLE token the a question-mark (u003f)
  followed by zero or more NUMERIC characters.
</b></blockquote><a name="H40320"></a>
<p>
  A "parameter name" is defined to be a sequence of one or more
  characters that consists of
  ALPHANUMERIC characters and/or dollar-signs (u0025) intermixed with
  pairs of colons (u003a) and optionally followed by any sequence
  of non-zero, non-WHITESPACE characters enclosed in parentheses
  (u0028 and u0029).
</p><blockquote><b>H40320:</b>
  SQLite shall recognize as a VARIABLE token one of the characters
  at-sign (u0040), dollar-sign (u0024), or colon (u003a) followed
  by a parameter name.
</b></blockquote><a name="H40330"></a>
<blockquote><b>H40330:</b>
  SQLite shall recognize as a VARIABLE token the shape-sign (u0023)
  followed by a parameter name that does not begin with a
  NUMERIC character.
</b></blockquote><a name="L42040"></a>
<p>
  The REGISTER token is a special token used internally.  It does not
  appear as part of the published user interface.  Hence, the following
  is a low-level requirement:
</p><blockquote><b>L42040:</b>
  SQLite shall recognize as a REGISTER token a sharp-sign (u0023)
  followed by one or more NUMERIC characters.