You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mod.rs
    path of file: ./repos/cnosdb/query_server/query/benches/data_utils
    
    the code of the file until where you have to start completion: use std::sync::Arc;

use arrow::array::{Float32Array, Float64Array, StringArray, UInt64Array};
use arrow::datatypes::{DataType, Field, Schema, SchemaRef};
use arrow::record_batch::RecordBatch;
use datafusion::arrow;
use datafusion::arrow::array::TimestampNanosecondArray;
use datafusion::arrow::datatypes::TimeUnit;
use datafusion::datasource::MemTable;
use datafusio
    
pub fn create_schema() -> Schema {
    Schema::new(vec![
        Field::new("ts", DataType::Timestamp(TimeUnit::Nanosecond, None), true),
        Field::new("utf8", DataType::Utf8, true),
        Field::new("f32", DataType::Float32, true),
        Field::new("f64", DataType::Float64, true),
        // This field will contain integers randomly selected from a large
        // range of values, i.e. [0, u64::MAX], such that there are none (or
        // very few) repeated values.
        Field::new("u64_wide", DataType::UInt64, true),
        // This field will contain integers randomly selected from a narrow
        // range of values such that there are a few distinct values, but they
        // are repeated often.
        Field::new("u64_narrow", DataType::UInt64, true),
    ])
}