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
)
)
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
usingClause,
ref nestedLevel);
}
return(usingClause);
}
public TSQLSelectClause Parse(ITSQLTokenizer tokenizer)
{
TSQLSelectClause select = new TSQLSelectClause();
if (!tokenizer.Current.IsKeyword(TSQLKeywords.SELECT))
{
throw new InvalidOperationException("SELECT expected.");
}
select.Tokens.Add(tokenizer.Current);
// can contain ALL, DISTINCT, TOP, PERCENT, WITH TIES, AS
// ends with FROM, semicolon, or keyword other than those listed above, when used outside of parens
// recursively walk down and back up parens
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
(
TSQLKeywords.INTO,
TSQLKeywords.FROM,
TSQLKeywords.WHERE,
TSQLKeywords.GROUP,
TSQLKeywords.HAVING,
TSQLKeywords.ORDER,
TSQLKeywords.UNION,
TSQLKeywords.EXCEPT,
TSQLKeywords.INTERSECT,
TSQLKeywords.FOR,
TSQLKeywords.OPTION
) &&
!tokenizer.Current.AsKeyword.Keyword.IsStatementStart()
)
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
select,
ref nestedLevel);
}
return(select);
}
public TSQLFromClause Parse(ITSQLTokenizer tokenizer)
{
TSQLFromClause from = new TSQLFromClause();
if (!tokenizer.Current.IsKeyword(TSQLKeywords.FROM))
{
throw new InvalidOperationException("FROM expected.");
}
from.Tokens.Add(tokenizer.Current);
// derived tables
// TVF
int nestedLevel = 0;
while (
tokenizer.MoveNext() &&
!(
tokenizer.Current.Type == TSQLTokenType.Character &&
tokenizer.Current.AsCharacter.Character == TSQLCharacters.Semicolon
) &&
!(
nestedLevel == 0 &&
tokenizer.Current.Type == TSQLTokenType.Character &&
tokenizer.Current.AsCharacter.Character == TSQLCharacters.CloseParentheses
) &&
(
nestedLevel > 0 ||
tokenizer.Current.Type != TSQLTokenType.Keyword ||
(
tokenizer.Current.Type == TSQLTokenType.Keyword &&
!tokenizer.Current.AsKeyword.Keyword.In
(
TSQLKeywords.WHERE,
TSQLKeywords.GROUP,
TSQLKeywords.HAVING,
TSQLKeywords.ORDER,
TSQLKeywords.UNION,
TSQLKeywords.EXCEPT,
TSQLKeywords.INTERSECT,
TSQLKeywords.FOR,
TSQLKeywords.OPTION
) &&
!tokenizer.Current.AsKeyword.Keyword.IsStatementStart()
)
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
from,
ref nestedLevel);
}
return(from);
}
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()
)
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
set,
ref nestedLevel);
}
return(set);
}
public TSQLWhereClause Parse(ITSQLTokenizer tokenizer)
{
TSQLWhereClause where = new TSQLWhereClause();
if (!tokenizer.Current.IsKeyword(TSQLKeywords.WHERE))
{
throw new InvalidOperationException("WHERE expected.");
}
where.Tokens.Add(tokenizer.Current);
// subqueries
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
(
TSQLKeywords.GROUP,
TSQLKeywords.HAVING,
TSQLKeywords.UNION,
TSQLKeywords.EXCEPT,
TSQLKeywords.INTERSECT,
TSQLKeywords.ORDER,
TSQLKeywords.FOR,
TSQLKeywords.OPTION
) &&
!tokenizer.Current.AsKeyword.Keyword.IsStatementStart()
)
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
where,
ref nestedLevel);
}
return(where);
}
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;
while (
tokenizer.MoveNext() &&
!(
nestedLevel == 0 &&
tokenizer.Current.IsCharacter(TSQLCharacters.CloseParentheses)
) &&
(
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
)
)
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
with,
ref nestedLevel);
}
return(with);
}
public TSQLOrderByClause Parse(ITSQLTokenizer tokenizer)
{
TSQLOrderByClause orderBy = new TSQLOrderByClause();
if (!tokenizer.Current.IsKeyword(TSQLKeywords.ORDER))
{
throw new InvalidOperationException("ORDER expected.");
}
orderBy.Tokens.Add(tokenizer.Current);
// subqueries
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
(
TSQLKeywords.FOR,
TSQLKeywords.OPTION
) &&
!tokenizer.Current.AsKeyword.Keyword.IsStatementStart()
)
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
orderBy,
ref nestedLevel);
}
return(orderBy);
}
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
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
into,
ref nestedLevel);
}
return(into);
}
/// <summary>
/// This reads recursively through parenthesis and returns when it hits
/// one of the stop words outside of any nested parenthesis.
/// </summary>
public static void ReadUntilStop(
ITSQLTokenizer tokenizer,
TSQLExpression expression,
List <TSQLFutureKeywords> futureKeywords,
List <TSQLKeywords> keywords,
bool lookForStatementStarts)
{
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 &&
!futureKeywords.Any(fk => tokenizer.Current.IsFutureKeyword(fk))
) ||
(
tokenizer.Current.Type == TSQLTokenType.Keyword &&
!keywords.Any(k => tokenizer.Current.AsKeyword.Keyword == k) &&
!(
lookForStatementStarts &&
tokenizer.Current.AsKeyword.Keyword.IsStatementStart()
)
)
))
{
TSQLSubqueryHelper.RecurseParens(
tokenizer,
expression,
ref nestedLevel);
}
}
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;
}
}
TSQLSubqueryHelper.RecurseParens(
tokenizer,
with,
ref nestedLevel);
}
return(with);
}
