public TSQLUsingClause Parse(ITSQLTokenizer tokenizer)
{
TSQLUsingClause usingClause = new TSQLUsingClause();
if (!tokenizer.Current.IsFutureKeyword(TSQLFutureKeywords.USING))
{
throw new InvalidOperationException("USING expected.");
}
usingClause.Tokens.Add(tokenizer.Current);
/* can contain:
*
* <table_source> ::=
* {
* table_or_view_name [ [ AS ] table_alias ] [ <tablesample_clause> ]
* [ WITH ( table_hint [ [ , ]...n ] ) ]
* | rowset_function [ [ AS ] table_alias ]
* [ ( bulk_column_alias [ ,...n ] ) ]
* | user_defined_function [ [ AS ] table_alias ]
* | OPENXML <openxml_clause>
* | derived_table [ AS ] table_alias [ ( column_alias [ ,...n ] ) ]
* | <joined_table>
* | <pivoted_table>
* | <unpivoted_table>
* }
* https://docs.microsoft.com/en-us/sql/t-sql/statements/merge-transact-sql?view=sql-server-ver15#syntax
*/
int nestedLevel = 0;
while (
tokenizer.MoveNext() &&
!tokenizer.Current.IsCharacter(TSQLCharacters.Semicolon) &&
!(
nestedLevel == 0 &&
tokenizer.Current.IsCharacter(TSQLCharacters.CloseParentheses)
) &&
(
nestedLevel > 0 ||
tokenizer.Current.Type != TSQLTokenType.Keyword ||
(
tokenizer.Current.Type == TSQLTokenType.Keyword &&
!tokenizer.Current.AsKeyword.Keyword.In
(
// ON is required in MERGE statement after USING
TSQLKeywords.ON
)
)
))
{
TSQLTokenParserHelper.RecurseParens(
tokenizer,
usingClause,
ref nestedLevel);
}
return(usingClause);
}
public TSQLSetClause Parse(ITSQLTokenizer tokenizer)
{
TSQLSetClause set = new TSQLSetClause();
if (!tokenizer.Current.IsKeyword(TSQLKeywords.SET))
{
throw new InvalidOperationException("SET expected.");
}
set.Tokens.Add(tokenizer.Current);
// TODO: parse this rare but valid horror scenario
// update output
// set output.output = 1
// output deleted.*
// maybe create assignment expression parser?
int nestedLevel = 0;
while (
tokenizer.MoveNext() &&
!tokenizer.Current.IsCharacter(TSQLCharacters.Semicolon) &&
!(
nestedLevel == 0 &&
tokenizer.Current.IsCharacter(TSQLCharacters.CloseParentheses)
) &&
(
nestedLevel > 0 ||
(
tokenizer.Current.Type != TSQLTokenType.Keyword &&
!tokenizer.Current.IsFutureKeyword(TSQLFutureKeywords.OUTPUT)
) ||
(
tokenizer.Current.Type == TSQLTokenType.Keyword &&
!tokenizer.Current.AsKeyword.Keyword.In
(
TSQLKeywords.FROM,
TSQLKeywords.WHERE,
TSQLKeywords.OPTION
) &&
!tokenizer.Current.AsKeyword.Keyword.IsStatementStart()
)
))
{
TSQLTokenParserHelper.RecurseParens(
tokenizer,
set,
ref nestedLevel);
}
return(set);
}
public TSQLIntoClause Parse(ITSQLTokenizer tokenizer)
{
TSQLIntoClause into = new TSQLIntoClause();
if (!tokenizer.Current.IsKeyword(TSQLKeywords.INTO))
{
throw new InvalidOperationException("INTO expected.");
}
into.Tokens.Add(tokenizer.Current);
int nestedLevel = 0;
while (
tokenizer.MoveNext() &&
!tokenizer.Current.IsCharacter(TSQLCharacters.Semicolon) &&
!(
nestedLevel == 0 &&
tokenizer.Current.IsCharacter(TSQLCharacters.CloseParentheses)
) &&
(
nestedLevel > 0 ||
tokenizer.Current.Type == TSQLTokenType.Identifier ||
tokenizer.Current.IsCharacter(TSQLCharacters.Period) ||
tokenizer.Current.IsCharacter(TSQLCharacters.OpenParentheses) ||
tokenizer.Current.Type == TSQLTokenType.Whitespace ||
tokenizer.Current.Type == TSQLTokenType.SingleLineComment ||
tokenizer.Current.Type == TSQLTokenType.MultilineComment
))
{
TSQLTokenParserHelper.RecurseParens(
tokenizer,
into,
ref nestedLevel);
}
return(into);
}
public TSQLWithClause Parse(ITSQLTokenizer tokenizer)
{
TSQLWithClause with = new TSQLWithClause();
if (!tokenizer.Current.IsKeyword(TSQLKeywords.WITH))
{
throw new InvalidOperationException("WITH expected.");
}
with.Tokens.Add(tokenizer.Current);
// subqueries
int nestedLevel = 0;
int parenCount = 0;
int identifierCount = 0;
bool afterAs = false;
while (
tokenizer.MoveNext() &&
!tokenizer.Current.IsCharacter(TSQLCharacters.Semicolon) &&
!(
nestedLevel == 0 &&
tokenizer.Current.IsCharacter(TSQLCharacters.CloseParentheses)
) &&
!(
// only allow a set of parens at root level
// if it's following an AS
// or if it's the column list between the CTE name and the AS
nestedLevel == 0 &&
tokenizer.Current.IsCharacter(TSQLCharacters.OpenParentheses) &&
afterAs &&
parenCount >= identifierCount
) &&
(
nestedLevel > 0 ||
tokenizer.Current.Type != TSQLTokenType.Keyword ||
(
tokenizer.Current.Type == TSQLTokenType.Keyword &&
!tokenizer.Current.AsKeyword.Keyword.In
(
TSQLKeywords.SELECT,
TSQLKeywords.INSERT,
TSQLKeywords.UPDATE,
TSQLKeywords.DELETE,
TSQLKeywords.MERGE
)
)
))
{
if (nestedLevel == 0)
{
if (afterAs && tokenizer.Current.IsCharacter(TSQLCharacters.OpenParentheses))
{
parenCount++;
}
else if (tokenizer.Current.Type == TSQLTokenType.Identifier)
{
identifierCount++;
afterAs = false;
}
else if (tokenizer.Current.IsKeyword(TSQLKeywords.AS))
{
afterAs = true;
}
}
TSQLTokenParserHelper.RecurseParens(
tokenizer,
with,
ref nestedLevel);
}
return(with);
}
