public static bool TryParseUntilFirstMsSqlSelectColumn(this IEnumerator<SqlToken> tokenEnum, out SqlToken selectToken, out bool isDistinct)
{
selectToken = null;
isDistinct = false;
while (tokenEnum.TryParseUntil("select"))
{
selectToken = tokenEnum.Current;
if (!tokenEnum.MoveNext()) return false;
// [ DISTINCT | ALL ]
if (tokenEnum.Current.Equals("distinct", StringComparison.InvariantCultureIgnoreCase))
{
isDistinct = true;
if (!tokenEnum.MoveNext()) return false;
}
else if (tokenEnum.Current.Equals("all", StringComparison.InvariantCultureIgnoreCase))
{
if (!tokenEnum.MoveNext()) return false;
}
// [ TOP { integer | ( expression ) } [PERCENT] [ WITH TIES ] ]
if (tokenEnum.Current.Equals("top", StringComparison.InvariantCultureIgnoreCase))
{
if (!tokenEnum.MoveNext()) return false;
if (tokenEnum.Current.TokenType == SqlTokenType.BracketOpen)
{
do
{
if (!tokenEnum.MoveNext()) return false;
} while (tokenEnum.Current.TokenType != SqlTokenType.BracketClose);
}
if (!tokenEnum.MoveNext()) return false;
if (tokenEnum.Current.Equals("percent", StringComparison.InvariantCultureIgnoreCase))
{
if (!tokenEnum.MoveNext()) return false;
}
if (tokenEnum.Current.Equals("with", StringComparison.InvariantCultureIgnoreCase))
{
if (!tokenEnum.MoveNext()) return false;
if (tokenEnum.Current.Equals("ties", StringComparison.InvariantCultureIgnoreCase))
{
if (!tokenEnum.MoveNext()) return false;
}
}
}
if (!tokenEnum.Current.Value.StartsWith("@")) return true;
}
return false;
}
private bool TryGetColumnDefinition(string columnNameOrIndex, out ColumnDefinition result, SqlToken beginToken, SqlToken endToken)
{
if (!string.IsNullOrEmpty(columnNameOrIndex))
{
int columnIndex;
if (int.TryParse(columnNameOrIndex, out columnIndex) && columnIndex <= _columns.Count)
{
result = _columns[columnIndex - 1];
return true;
}
foreach (var column in _columns)
{
if (columnNameOrIndex.Equals(column.Name, StringComparison.InvariantCultureIgnoreCase)
|| columnNameOrIndex.Equals(column.Alias, StringComparison.InvariantCultureIgnoreCase))
{
result = column;
return true;
}
}
}
else
{
var sqlIndex = beginToken.SqlIndex;
var sqlLength = (endToken != null ? endToken.SqlIndex + endToken.Length : Sql.Length) - beginToken.SqlIndex;
var text = Sql.Substring(sqlIndex, sqlLength).ToString();
foreach (var column in _columns)
{
if (text.Equals(column.Name, StringComparison.InvariantCultureIgnoreCase) ||
text.Equals(column.Alias, StringComparison.InvariantCultureIgnoreCase) ||
text.Equals(Sql.Substring(column.SqlIndex, column.SqlLength).ToString(), StringComparison.InvariantCultureIgnoreCase))
{
result = column;
return true;
}
}
}
result = null;
return false;
}
private OrderDefinition ParseOrderDefinition(SqlToken beginToken, SqlToken endToken, SqlToken directionToken)
{
var isDescending = directionToken != null &&
directionToken.Equals("desc", StringComparison.InvariantCultureIgnoreCase);
var columnNameOrIndex = beginToken == endToken
? beginToken.Value
: null;
ColumnDefinition column;
if (!TryGetColumnDefinition(columnNameOrIndex, out column, beginToken, endToken))
{
// Column appears in order by clause, but not in select clause
column = ParseOrderColumnDefinition(beginToken, endToken, "__c" + _nextOrderAliasIndex++);
}
return new OrderDefinition(column, isDescending);
}
private ColumnDefinition ParseOrderColumnDefinition(SqlToken beginToken, SqlToken endToken, string alias)
{
var sqlIndex = beginToken.SqlIndex;
var sqlLength = (endToken != null ? endToken.SqlIndex + endToken.Length : Sql.Length) - beginToken.SqlIndex;
return new ColumnDefinition(sqlIndex, sqlLength, null, alias, false);
}
private ColumnDefinition ParseSelectColumnDefinition(SqlToken beginToken, SqlToken endToken, SqlToken aliasToken)
{
var name = beginToken == endToken
? beginToken.Value
: null;
var alias = aliasToken.Value;
var dotIndex = alias.LastIndexOf('.');
alias = dotIndex >= 0
? alias.Substring(dotIndex + 1)
: alias;
var sqlIndex = beginToken.SqlIndex;
var sqlLength = (endToken != null ? endToken.SqlIndex + endToken.Length : Sql.Length) - beginToken.SqlIndex;
return new ColumnDefinition(sqlIndex, sqlLength, name, alias, true);
}
public static bool TryParseUntilFirstOrderColumn(this IEnumerator<SqlToken> tokenEnum, out SqlToken orderToken)
{
if (tokenEnum.TryParseUntil("order"))
{
orderToken = tokenEnum.Current;
if (tokenEnum.MoveNext())
{
return tokenEnum.Current.Equals("by", StringComparison.InvariantCultureIgnoreCase)
? tokenEnum.MoveNext()
: false;
}
}
orderToken = null;
return false;
}
private OrderDefinition ParseOrderDefinition(SqlToken beginToken, SqlToken endToken, SqlToken directionToken)
{
var isDescending = directionToken != null &&
directionToken.Equals("desc", StringComparison.InvariantCultureIgnoreCase);
var columnNameOrIndex = beginToken == endToken
? beginToken.Value
: null;
ColumnDefinition column;
if (!TryGetColumnDefinition(columnNameOrIndex, out column, beginToken, endToken))
{
// Column appears in order by clause, but not in select clause
column = ParseOrderColumnDefinition(beginToken, endToken, "__c" + _nextOrderAliasIndex++);
}
return(new OrderDefinition(column, isDescending));
}
private bool TryGetColumnDefinition(string columnNameOrIndex, out ColumnDefinition result, SqlToken beginToken, SqlToken endToken)
{
if (!string.IsNullOrEmpty(columnNameOrIndex))
{
int columnIndex;
if (int.TryParse(columnNameOrIndex, out columnIndex) && columnIndex <= _columns.Count)
{
result = _columns[columnIndex - 1];
return(true);
}
foreach (var column in _columns)
{
if (columnNameOrIndex.Equals(column.Name, StringComparison.InvariantCultureIgnoreCase) ||
columnNameOrIndex.Equals(column.Alias, StringComparison.InvariantCultureIgnoreCase))
{
result = column;
return(true);
}
}
}
else
{
var sqlIndex = beginToken.SqlIndex;
var sqlLength = (endToken != null ? endToken.SqlIndex + endToken.Length : Sql.Length) - beginToken.SqlIndex;
var text = Sql.ToString(sqlIndex, sqlLength);
foreach (var column in _columns)
{
if (text.Equals(column.Name, StringComparison.InvariantCultureIgnoreCase) ||
text.Equals(column.Alias, StringComparison.InvariantCultureIgnoreCase) ||
text.Equals(Sql.ToString(column.SqlIndex, column.SqlLength), StringComparison.InvariantCultureIgnoreCase))
{
result = column;
return(true);
}
}
}
result = null;
return(false);
}
private IEnumerable <OrderDefinition> ParseOrderDefinitions(IEnumerator <SqlToken> tokenEnum)
{
int blockLevel = 0;
SqlToken orderBeginToken = null;
SqlToken orderEndToken = null;
SqlToken directionToken = null;
SqlToken prevToken = null;
do
{
var token = tokenEnum.Current;
if (token == null)
{
break;
}
if (token.TokenType == SqlTokenType.Whitespace)
{
continue;
}
orderBeginToken = orderBeginToken ?? token;
switch (token.TokenType)
{
case SqlTokenType.BracketOpen:
blockLevel++;
break;
case SqlTokenType.BracketClose:
blockLevel--;
break;
case SqlTokenType.Text:
if (blockLevel != 0)
{
break;
}
if (token.Equals("asc", StringComparison.InvariantCultureIgnoreCase) ||
token.Equals("desc", StringComparison.InvariantCultureIgnoreCase))
{
orderEndToken = prevToken;
directionToken = token;
}
break;
case SqlTokenType.DelimitedText:
if (blockLevel != 0)
{
break;
}
break;
case SqlTokenType.Comma:
if (blockLevel != 0)
{
break;
}
yield return(ParseOrderDefinition(orderBeginToken, orderEndToken ?? prevToken, directionToken));
orderBeginToken = orderEndToken = directionToken = null;
break;
}
prevToken = token;
} while (tokenEnum.MoveNext());
if (orderBeginToken != null)
{
yield return(ParseOrderDefinition(orderBeginToken, orderEndToken ?? prevToken, directionToken));
}
}
private ColumnDefinition ParseSelectColumnDefinition(SqlToken beginToken, SqlToken endToken, SqlToken aliasToken)
{
var name = beginToken == endToken
? beginToken.Value
: null;
var alias = aliasToken.Value;
var dotIndex = alias.LastIndexOf('.');
alias = dotIndex >= 0
? alias.Substring(dotIndex + 1)
: alias;
var sqlIndex = beginToken.SqlIndex;
var sqlLength = (endToken != null ? endToken.SqlIndex + endToken.Length : Sql.Length) - beginToken.SqlIndex;
return(new ColumnDefinition(sqlIndex, sqlLength, name, alias, true));
}
private IEnumerable <ColumnDefinition> ParseColumnDefinitions(IEnumerator <SqlToken> tokenEnum)
{
int blockLevel = 0;
SqlToken columnBeginToken = null;
SqlToken columnEndToken = null;
SqlToken columnAliasToken = null;
SqlToken prevToken = null;
do
{
var token = tokenEnum.Current;
if (token == null)
{
break;
}
columnBeginToken = columnBeginToken ?? token;
switch (token.TokenType)
{
case SqlTokenType.BracketOpen:
blockLevel++;
break;
case SqlTokenType.BracketClose:
blockLevel--;
break;
case SqlTokenType.Text:
if (blockLevel != 0)
{
break;
}
if (token.Equals(",", StringComparison.InvariantCultureIgnoreCase))
{
if (columnAliasToken != null)
{
yield return(ParseSelectColumnDefinition(columnBeginToken, columnEndToken ?? columnAliasToken, columnAliasToken));
}
}
if (token.Equals("from", StringComparison.InvariantCultureIgnoreCase))
{
if (columnAliasToken != null)
{
yield return(ParseSelectColumnDefinition(columnBeginToken, columnEndToken ?? columnAliasToken, columnAliasToken));
}
yield break;
}
if (token.Equals("as", StringComparison.InvariantCultureIgnoreCase))
{
columnEndToken = prevToken;
}
columnAliasToken = token;
break;
case SqlTokenType.DelimitedText:
if (blockLevel != 0)
{
break;
}
columnAliasToken = token;
break;
case SqlTokenType.Comma:
if (blockLevel != 0)
{
break;
}
if (columnAliasToken != null)
{
yield return(ParseSelectColumnDefinition(columnBeginToken, columnEndToken ?? columnAliasToken, columnAliasToken));
}
columnBeginToken = columnEndToken = columnAliasToken = null;
break;
}
prevToken = token;
} while (tokenEnum.MoveNext());
if (columnAliasToken != null)
{
yield return(ParseSelectColumnDefinition(columnBeginToken, columnEndToken ?? columnAliasToken, columnAliasToken));
}
}
public static bool TryParseUntilFirstMsSqlSelectColumn(this IEnumerator <SqlToken> tokenEnum, out SqlToken selectToken, out bool isDistinct)
{
selectToken = null;
isDistinct = false;
while (tokenEnum.TryParseUntil("select"))
{
selectToken = tokenEnum.Current;
if (!tokenEnum.MoveNext())
{
return(false);
}
// [ DISTINCT | ALL ]
if (tokenEnum.Current.Equals("distinct", StringComparison.OrdinalIgnoreCase))
{
isDistinct = true;
if (!tokenEnum.MoveNext())
{
return(false);
}
}
else if (tokenEnum.Current.Equals("all", StringComparison.OrdinalIgnoreCase))
{
if (!tokenEnum.MoveNext())
{
return(false);
}
}
// [ TOP { integer | ( expression ) } [PERCENT] [ WITH TIES ] ]
if (tokenEnum.Current.Equals("top", StringComparison.OrdinalIgnoreCase))
{
if (!tokenEnum.MoveNext())
{
return(false);
}
if (tokenEnum.Current.TokenType == SqlTokenType.BracketOpen)
{
do
{
if (!tokenEnum.MoveNext())
{
return(false);
}
} while (tokenEnum.Current.TokenType != SqlTokenType.BracketClose);
}
if (!tokenEnum.MoveNext())
{
return(false);
}
if (tokenEnum.Current.Equals("percent", StringComparison.OrdinalIgnoreCase))
{
if (!tokenEnum.MoveNext())
{
return(false);
}
}
if (tokenEnum.Current.Equals("with", StringComparison.OrdinalIgnoreCase))
{
if (!tokenEnum.MoveNext())
{
return(false);
}
if (tokenEnum.Current.Equals("ties", StringComparison.OrdinalIgnoreCase))
{
if (!tokenEnum.MoveNext())
{
return(false);
}
}
}
}
if (!tokenEnum.Current.Value.StartsWith('@'))
{
return(true);
}
}
return(false);
}
public static bool TryParseUntilFirstOrderColumn(this IEnumerator <SqlToken> tokenEnum, out SqlToken orderToken)
{
if (tokenEnum.TryParseUntil("order"))
{
orderToken = tokenEnum.Current;
if (tokenEnum.MoveNext())
{
return(tokenEnum.Current.Equals("by", StringComparison.InvariantCultureIgnoreCase)
? tokenEnum.MoveNext()
: false);
}
}
orderToken = null;
return(false);
}