public static bool KeywordPrecedesTable(SqlLiteral value)
{
if (value == null || value.Type != SqlType.Keyword)
{
return(false);
}
switch (value.Text.ToLowerInvariant())
{
case "from":
case "update":
return(true);
}
if (value.Text.EndsWith("join", StringComparison.OrdinalIgnoreCase) ||
value.Text.EndsWith("apply", StringComparison.OrdinalIgnoreCase) ||
value.Text.EndsWith("into", StringComparison.OrdinalIgnoreCase))
{
return(true);
}
return(false);
}
public IEnumerable <SqlLiteral> BasicEnumerator()
{
_i = 0;
while (_i < _text.Length)
{
switch (_state)
{
case State.Start:
_current = new SqlLiteral();
if (StartsWith('/', '*'))
{
_current.StartOffset = _i;
_i++;
_state = State.CommentMulti;
}
else if (StartsWith('-', '-'))
{
_current.StartOffset = _i;
_i++;
_state = State.CommentLine;
}
else if (StartsWith('N', '\''))
{
_current.StartOffset = _i;
_i++;
_state = State.StringLiteral;
}
else if (StartsWith('0', 'x'))
{
_current.StartOffset = _i;
_i++;
_state = State.BinaryLiteral;
}
else if (_text[_i] == '[')
{
_current.StartOffset = _i;
_state = State.IdentifierBracket;
}
else if (_text[_i] == '"')
{
_current.StartOffset = _i;
_state = State.IdentifierQuote;
}
else if (_text[_i] == '\'')
{
_current.StartOffset = _i;
_state = State.StringLiteral;
}
else if (_text[_i] == '$')
{
_current.StartOffset = _i;
_state = State.NumericLiteral;
}
else if (_text[_i] == '@')
{
_current.StartOffset = _i;
_state = State.Identifier;
}
else if (char.IsDigit(_text[_i]))
{
_current.StartOffset = _i;
_state = State.NumericLiteral;
}
else if (char.IsLetter(_text[_i]) || _text[_i] == '_')
{
_current.StartOffset = _i;
_state = State.Identifier;
}
else if (char.IsWhiteSpace(_text[_i]))
{
_state = State.Whitespace;
}
else
{
yield return(new SqlLiteral()
{
StartOffset = _i,
Text = _text[_i].ToString(),
Type = SqlType.Operator
});
}
break;
case State.BinaryLiteral:
if (!IsHexDigit(_text[_i]))
{
_current.Text = _text.Substring(_current.StartOffset, _i - _current.StartOffset);
_current.Type = SqlType.Binary;
yield return(_current);
_i--;
_state = State.Start;
}
break;
case State.CommentLine:
if (_text[_i] == '\r' || _text[_i] == '\n')
{
_current.Text = _text.Substring(_current.StartOffset, _i - _current.StartOffset);
_current.Type = SqlType.Comment;
yield return(_current);
_i--;
_state = State.Start;
}
break;
case State.CommentMulti:
if (StartsWith('*', '/'))
{
_i++;
_current.Text = _text.Substring(_current.StartOffset, _i + 1 - _current.StartOffset);
_current.Type = SqlType.Comment;
yield return(_current);
_state = State.Start;
}
break;
case State.Identifier:
if (!char.IsLetterOrDigit(_text[_i]) && _text[_i] != '_')
{
_current.Text = _text.Substring(_current.StartOffset, _i - _current.StartOffset);
_current.Type = SqlType.Identifier;
yield return(_current);
_i--;
_state = State.Start;
}
break;
case State.IdentifierBracket:
if (_text[_i] == ']')
{
_current.Text = _text.Substring(_current.StartOffset, _i + 1 - _current.StartOffset);
_current.Type = SqlType.Identifier;
yield return(_current);
_state = State.Start;
}
break;
case State.IdentifierQuote:
if (_text[_i] == '"')
{
_current.Text = _text.Substring(_current.StartOffset, _i + 1 - _current.StartOffset);
_current.Type = SqlType.Identifier;
yield return(_current);
_state = State.Start;
}
break;
case State.NumericLiteral:
if (_text[_i] == '.')
{
_state = State.NumDecimalLiteral;
}
else if (StartsWith('e', '+') || StartsWith('e', '-') ||
StartsWith('E', '+') || StartsWith('E', '-'))
{
_i++;
_state = State.NumExponentLiteral;
}
else if (_text[_i] == 'e' || _text[_i] == 'E')
{
_i++;
_state = State.NumExponentLiteral;
}
else if (!char.IsDigit(_text[_i]))
{
_current.Text = _text.Substring(_current.StartOffset, _i - _current.StartOffset);
_current.Type = SqlType.Number;
yield return(_current);
_i--;
_state = State.Start;
}
break;
case State.NumDecimalLiteral:
if (StartsWith('e', '+') || StartsWith('e', '-') ||
StartsWith('E', '+') || StartsWith('E', '-'))
{
_i++;
_state = State.NumExponentLiteral;
}
else if (_text[_i] == 'e' || _text[_i] == 'E')
{
_i++;
_state = State.NumExponentLiteral;
}
else if (!char.IsDigit(_text[_i]))
{
_current.Text = _text.Substring(_current.StartOffset, _i - _current.StartOffset);
_current.Type = SqlType.Number;
yield return(_current);
_i--;
_state = State.Start;
}
break;
case State.NumExponentLiteral:
if (!char.IsDigit(_text[_i]))
{
_current.Text = _text.Substring(_current.StartOffset, _i - _current.StartOffset);
_current.Type = SqlType.Number;
yield return(_current);
_i--;
_state = State.Start;
}
break;
case State.StringLiteral:
if (StartsWith('\'', '\''))
{
_i++;
}
else if (_text[_i] == '\'')
{
_current.Text = _text.Substring(_current.StartOffset, _i + 1 - _current.StartOffset);
_current.Type = SqlType.String;
yield return(_current);
_state = State.Start;
}
break;
case State.Whitespace:
if (!char.IsWhiteSpace(_text[_i]))
{
_i--;
_state = State.Start;
}
break;
}
_i++;
}
if (_state != State.Start && _current.StartOffset >= 0)
{
_current.Text = _text.Substring(_current.StartOffset);
switch (_state)
{
case State.BinaryLiteral:
_current.Type = SqlType.Binary;
break;
case State.Start:
case State.Whitespace:
case State.CommentLine:
case State.CommentMulti:
_current.Type = SqlType.Comment;
break;
case State.Identifier:
case State.IdentifierBracket:
case State.IdentifierQuote:
_current.Type = SqlType.Identifier;
break;
case State.NumDecimalLiteral:
case State.NumericLiteral:
case State.NumExponentLiteral:
_current.Type = SqlType.Number;
break;
case State.StringLiteral:
_current.Type = SqlType.String;
break;
}
yield return(_current);
}
}
public IEnumerator <SqlNode> GetEnumerator()
{
SqlLiteral prevLiteral = null;
SqlName prevName = null;
var en = MarkKeywords().GetEnumerator();
if (!en.MoveNext())
{
yield break;
}
prevLiteral = en.Current;
while (en.MoveNext())
{
if (prevLiteral != null && (KeywordPrecedesTable(prevLiteral) ||
prevLiteral.Text.StartsWith("create ", StringComparison.OrdinalIgnoreCase)))
{
prevName = new SqlName();
prevName.IsTable = true;
yield return(prevLiteral);
if (prevName.TryAdd(en.Current))
{
prevLiteral = null;
}
else
{
prevLiteral = en.Current;
prevName = null;
}
}
else if (prevLiteral != null && prevLiteral.Type == SqlType.Identifier && en.Current.Text == ".")
{
prevName = new SqlName();
if (prevName.TryAdd(prevLiteral) && prevName.TryAdd(en.Current))
{
prevLiteral = null;
}
else
{
yield return(prevLiteral);
prevLiteral = en.Current;
prevName = null;
}
}
else if (prevName != null)
{
if (!prevName.TryAdd(en.Current))
{
yield return(prevName);
prevName = null;
prevLiteral = en.Current;
}
}
else
{
yield return(prevLiteral);
prevLiteral = en.Current;
}
}
if (prevLiteral != null)
{
yield return(prevLiteral);
}
if (prevName != null)
{
yield return(prevName);
}
}