ClickHouse/src/Parsers/ParserShowColumnsQuery.cpp
2023-05-02 13:16:15 +00:00

98 lines
2.8 KiB
C++

#include <Parsers/ParserShowColumnsQuery.h>
#include <Parsers/ASTIdentifier_fwd.h>
#include <Parsers/ASTLiteral.h>
#include <Parsers/ASTShowColumnsQuery.h>
#include <Parsers/CommonParsers.h>
#include <Parsers/ExpressionElementParsers.h>
#include <Parsers/ExpressionListParsers.h>
#include <boost/algorithm/string.hpp>
namespace DB
{
bool ParserShowColumnsQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
{
ASTPtr like;
ASTPtr from1;
ASTPtr from2;
String from1_str;
String from2_str;
auto query = std::make_shared<ASTShowColumnsQuery>();
if (!ParserKeyword("SHOW").ignore(pos, expected))
return false;
if (ParserKeyword("EXTENDED").ignore(pos, expected))
query->extended = true;
if (ParserKeyword("FULL").ignore(pos, expected))
query->full = true;
if (!(ParserKeyword("COLUMNS").ignore(pos, expected) || ParserKeyword("FIELDS").ignore(pos, expected)))
return false;
if (ParserKeyword("FROM").ignore(pos, expected) || ParserKeyword("IN").ignore(pos, expected))
{
if (!ParserCompoundIdentifier().parse(pos, from1, expected))
return false;
}
else
return false;
tryGetIdentifierNameInto(from1, from1_str);
bool abbreviated_form = from1_str.contains("."); // FROM database.table
if (abbreviated_form)
{
std::vector<String> split;
boost::split(split, from1_str, boost::is_any_of("."));
query->database = split[0];
query->table = split[1];
}
else
{
if (ParserKeyword("FROM").ignore(pos, expected) || ParserKeyword("IN").ignore(pos, expected))
if (!ParserIdentifier().parse(pos, from2, expected))
return false;
tryGetIdentifierNameInto(from2, from2_str);
query->table = from1_str;
query->database = from2_str;
}
if (ParserKeyword("NOT").ignore(pos, expected))
query->not_like = true;
if (bool insensitive = ParserKeyword("ILIKE").ignore(pos, expected); insensitive || ParserKeyword("LIKE").ignore(pos, expected))
{
if (insensitive)
query->case_insensitive_like = true;
if (!ParserStringLiteral().parse(pos, like, expected))
return false;
}
else if (query->not_like)
return false;
else if (ParserKeyword("WHERE").ignore(pos, expected))
if (!ParserExpressionWithOptionalAlias(false).parse(pos, query->where_expression, expected))
return false;
if (ParserKeyword("LIMIT").ignore(pos, expected))
if (!ParserExpressionWithOptionalAlias(false).parse(pos, query->limit_length, expected))
return false;
if (like)
query->like = like->as<ASTLiteral &>().value.safeGet<const String &>();
node = query;
return true;
}
}