#pragma once #include namespace DB { class Context; class IAST; using ASTPtr = std::shared_ptr; /** Check that table exists. Return single row with single column "result" of type UInt8 and value 0 or 1. */ class InterpreterExistsQuery : public IInterpreter { public: InterpreterExistsQuery(const ASTPtr & query_ptr_, const Context & context_) : query_ptr(query_ptr_), context(context_) {} BlockIO execute() override; static Block getSampleBlock(); private: ASTPtr query_ptr; const Context & context; BlockInputStreamPtr executeImpl(); }; }