如何生成受數據精度限制的模型，在Rails上按比例縮放紅寶石

Question

我正在嘗試生成以下名為PriceUsdOneMinIntervals的模型，但是無法正確應用格式以進行精確度和縮放，有人可以建議以下方法來糾正語法：

rails generate model PriceUsdOneMinInterval unix_timestamp:integer usd_high:decimal :precision[20] :scale[8] usd_low:decimal :precision[20] :scale[8] usd_open:decimal :precision[20] :scale[8] usd_close:decimal :precision[20] scale[8]

在進行上述聲明時，我已引用此 api。

Answer 1

嘗試這個

rails generate model PriceUsdOneMinInterval :unix_timestamp, :integer, 
:usd_high, :decimal, precision: 20, scale: 8, :usd_low, :decimal, precision: 20, 
scale: 8, :usd_open, :decimal, precision: 20, scale: 8, 
:usd_close, :decimal, precision: 20, scale: 8

要么

僅使用字段名稱和data_types生成遷移，然后更改即可更改遷移中的值

def change
    add_column :price_usd_one_min_intervals, :unix_timestamp, :integer
    add_column :price_usd_one_min_intervals, :usd_high, :decimal, precision: 20, :scale: 8
    add_column :price_usd_one_min_intervals, :usd_low, :decimal, precision: 20, scale: 8
    add_column :price_usd_one_min_intervals, :usd_open, :decimal, precision: 20, scale: 8
    add_column :price_usd_one_min_intervals, :usd_close, :decimal, precision: 20, scale: 8
end 

Answer 2

rails g model PriceUsdOneMinInterval \
unix_timestamp:integer \
'usd_high:decimal{20,8}' \
'usd_low:decimal{20,8}' \
'usd_open:decimal{20,8}' \
'usd_close:decimal{20,8}'