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#include <Parsers/ParserExplainQuery.h>
#include <Parsers/ASTExplainQuery.h>
#include <Parsers/CommonParsers.h>
#include <Parsers/ParserCreateQuery.h>
#include <Parsers/ParserSelectWithUnionQuery.h>
#include <Parsers/ParserInsertQuery.h>
#include <Parsers/ParserSetQuery.h>
#include <Parsers/ParserQuery.h>
#include <Parsers/ParserSystemQuery.h>
namespace DB
{
bool ParserExplainQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
{
ASTExplainQuery::ExplainKind kind;
ParserKeyword s_ast("AST");
ParserKeyword s_explain("EXPLAIN");
ParserKeyword s_syntax("SYNTAX");
ParserKeyword s_query_tree("QUERY TREE");
ParserKeyword s_pipeline("PIPELINE");
ParserKeyword s_plan("PLAN");
ParserKeyword s_estimates("ESTIMATE");
ParserKeyword s_table_override("TABLE OVERRIDE");
ParserKeyword s_current_transaction("CURRENT TRANSACTION");
if (s_explain.ignore(pos, expected))
{
kind = ASTExplainQuery::QueryPlan;
if (s_ast.ignore(pos, expected))
kind = ASTExplainQuery::ExplainKind::ParsedAST;
else if (s_syntax.ignore(pos, expected))
kind = ASTExplainQuery::ExplainKind::AnalyzedSyntax;
else if (s_query_tree.ignore(pos, expected))
kind = ASTExplainQuery::ExplainKind::QueryTree;
else if (s_pipeline.ignore(pos, expected))
kind = ASTExplainQuery::ExplainKind::QueryPipeline;
else if (s_plan.ignore(pos, expected))
kind = ASTExplainQuery::ExplainKind::QueryPlan;
else if (s_estimates.ignore(pos, expected))
kind = ASTExplainQuery::ExplainKind::QueryEstimates;
else if (s_table_override.ignore(pos, expected))
kind = ASTExplainQuery::ExplainKind::TableOverride;
else if (s_current_transaction.ignore(pos, expected))
kind = ASTExplainQuery::ExplainKind::CurrentTransaction;
}
else
return false;
auto explain_query = std::make_shared<ASTExplainQuery>(kind);
{
ASTPtr settings;
ParserSetQuery parser_settings(true);
auto begin = pos;
if (parser_settings.parse(pos, settings, expected))
explain_query->setSettings(std::move(settings));
else
pos = begin;
}
ParserCreateTableQuery create_p;
ParserSelectWithUnionQuery select_p;
ParserInsertQuery insert_p(end, allow_settings_after_format_in_insert);
ParserSystemQuery system_p;
ASTPtr query;
if (kind == ASTExplainQuery::ExplainKind::ParsedAST)
{
ParserQuery p(end, allow_settings_after_format_in_insert);
if (p.parse(pos, query, expected))
explain_query->setExplainedQuery(std::move(query));
else
return false;
}
else if (kind == ASTExplainQuery::ExplainKind::TableOverride)
{
ASTPtr table_function;
if (!ParserFunction(true, true).parse(pos, table_function, expected))
return false;
ASTPtr table_override;
if (!ParserTableOverrideDeclaration(false).parse(pos, table_override, expected))
return false;
explain_query->setTableFunction(table_function);
explain_query->setTableOverride(table_override);
}
else if (kind == ASTExplainQuery::ExplainKind::QueryTree)
{
if (select_p.parse(pos, query, expected))
explain_query->setExplainedQuery(std::move(query));
else
return false;
}
else if (kind == ASTExplainQuery::ExplainKind::CurrentTransaction)
{
/// Nothing to parse
}
else if (select_only)
{
if (select_p.parse(pos, query, expected))
explain_query->setExplainedQuery(std::move(query));
else
return false;
}
else if (select_p.parse(pos, query, expected) ||
create_p.parse(pos, query, expected) ||
insert_p.parse(pos, query, expected) ||
system_p.parse(pos, query, expected))
{
explain_query->setExplainedQuery(std::move(query));
}
else
{
return false;
}
node = std::move(explain_query);
return true;
}
}
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