ref #9436
Currently EPHEMERAL column requires an explicit default value provided on CREATE TABLE - we can allow implicit default there

{
public:
    const bool is_standalone;
    explicit ParserTableOverrideDeclaration(bool is_standalone_ = true) : is_standalone(is_standalone_) { }
protected:
    const char * getName() const override { return "table override declaration"; }
    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
};
class ParserTableOverridesDeclarationList : public IParserBase
{
protected:
    const char * getName() const override { return "table overrides declaration list"; }
    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
};
class ParserCreateDatabaseQuery : public IParserBase
{
protected:
    const char * getName() const override { return "CREATE DATABASE query"; }
    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
};
class ParserCreateViewQuery : public IParserBase
{
protected:
    const char * getName() const override { return "CREATE VIEW query"; }
    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
};
class ParserCreateDictionaryQuery : public IParserBase