ClickHouse/dbms/include/DB/Interpreters/InterpreterShowCreateQuery.h
2016-05-28 08:31:36 +03:00

75 lines
1.7 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#pragma once
#include <DB/Storages/IStorage.h>
#include <DB/Parsers/TablePropertiesQueriesASTs.h>
#include <DB/Parsers/formatAST.h>
#include <DB/Interpreters/Context.h>
#include <DB/Interpreters/IInterpreter.h>
#include <DB/DataStreams/OneBlockInputStream.h>
#include <DB/DataStreams/BlockIO.h>
#include <DB/DataStreams/copyData.h>
#include <DB/DataTypes/DataTypesNumberFixed.h>
#include <DB/DataTypes/DataTypeString.h>
namespace DB
{
/** Вернуть одну строку с одним столбцом statement типа String с текстом запроса, создающего указанную таблицу.
*/
class InterpreterShowCreateQuery : public IInterpreter
{
public:
InterpreterShowCreateQuery(ASTPtr query_ptr_, Context & context_)
: query_ptr(query_ptr_), context(context_) {}
BlockIO execute() override
{
BlockIO res;
res.in = executeImpl();
res.in_sample = getSampleBlock();
return res;
}
private:
ASTPtr query_ptr;
Context context;
Block getSampleBlock()
{
ColumnWithTypeAndName col;
col.name = "statement";
col.type = new DataTypeString;
col.column = col.type->createColumn();
Block block;
block.insert(col);
return block;
}
BlockInputStreamPtr executeImpl()
{
const ASTShowCreateQuery & ast = typeid_cast<const ASTShowCreateQuery &>(*query_ptr);
std::stringstream stream;
formatAST(*context.getCreateQuery(ast.database, ast.table), stream, 0, false, true);
String res = stream.str();
ColumnWithTypeAndName col;
col.name = "statement";
col.type = new DataTypeString;
col.column = std::make_shared<ColumnConstString>(1, res);
Block block;
block.insert(col);
return new OneBlockInputStream(block);
}
};
}