**Describe what's wrong**

We have a nested field in a table.
The table is created using SET flatten_nested = 0.
When the server is restarted the field is no longer nested (only flattened arrays appear).

**Does it reproduce on recent release?**

version 22.2.3.1

**How to reproduce**

Create a table using:

` 
SET flatten_nested = 0            
` 
` 
CREATE TABLE test.test    
    (     
        id String,  
       nested_field Nested (nf1 String, nf2 String)  
    ) ENGINE = MergeTree ORDER BY id  
`

Recover the table structure using describe:
`
describe test.test
`
`
name           type
id             String
nested_field   Nested(nf1 String, nf2 String) 
`

Restart click-house server.

Recover the table structure using describe:
`
 name               type            
 id                 String                                                                                          
 nested_field.nf1   Array(String)                                                                                   
 nested_field.nf2   Array(String)                                                                                   
`

*Expected behavior**

Recover the initial structure of the table not he flatenned one.


}
    }
    Block defaults_sample_block;
    
    if (!default_expr_list->children.empty())
        defaults_sample_block = validateColumnsDefaultsAndGetSampleBlock(default_expr_list, column_names_and_types, context_);
    bool sanity_check_compression_codecs = !attach && !context_->getSettingsRef().allow_suspicious_codecs;
    bool allow_experimental_codecs = attach || context_->getSettingsRef().allow_experimental_codecs;
    ColumnsDescription res;
    auto name_type_it = column_names_and_types.begin();
    for (auto ast_it = columns_ast.children.begin(); ast_it != columns_ast.children.end(); ++ast_it, ++name_type_it)
    {
        ColumnDescription column;
        auto & col_decl = (*ast_it)->as<ASTColumnDeclaration &>();
        column.name = col_decl.name;
        if (col_decl.default_expression)
        {
            ASTPtr default_expr =
                col_decl.default_specifier == "EPHEMERAL" && col_decl.default_expression->as<ASTLiteral>()->value.isNull() ?
                    std::make_shared<ASTLiteral>(DataTypeFactory::instance().get(col_decl.type)->getDefault()) :
                    col_decl.default_expression->clone();
            if (col_decl.type)
                column.type = name_type_it->type;
            else
                column.type = defaults_sample_block.getByName(column.name).type;
            column.default_desc.kind = columnDefaultKindFromString(col_decl.default_specifier);
            column.default_desc.expression = default_expr;
        }
        else if (col_decl.type)
            column.type = name_type_it->type;