使用SQL將單個列中存在的值分類為各自的數據類型？

Question

我一直試圖將單列中存在的set值（就像上面一樣）分類為數據類型。 問題是我正在使用Aster SQL環境（功能的可用性和整個環境非常有限）。 另一個問題是，該列中有很多垃圾值，許多符號，字符等，這使得很難對問題進行硬編碼。 結構類似於：

FeatureValue
123
24
15.6
17:15
abc
12/18/2014
17/222222           
abc1200                                
001001oo             
positve+              
+1                           

我希望解決方案是SQL查詢。 最終結果應類似於：

FeatureValue    Type
123             Numeric
24              Numeric
15.6            Numeric
17:15           String (?time)
abc             String
12/18/2014      Date
17/222222       String
abc1200         String
001001oo        String
positve+        String
+1              String

我編寫了一些代碼，但是這種解決方案不是很可靠。 我所做的是：

case 
            when upper(trim(feature_value)) not like '%A%' and
            upper(trim(feature_value)) not like '%B%' and
            upper(trim(feature_value)) not like '%C%' and
            upper(trim(feature_value)) not like '%D%' and
            upper(trim(feature_value)) not like '%E%' and
            upper(trim(feature_value)) not like '%F%' and
            upper(trim(feature_value)) not like '%G%' and
            upper(trim(feature_value)) not like '%H%' and
            upper(trim(feature_value)) not like '%I%' and
            upper(trim(feature_value)) not like '%J%' and
            upper(trim(feature_value)) not like '%K%' and
            upper(trim(feature_value)) not like '%L%' and
            upper(trim(feature_value)) not like '%M%' and
            upper(trim(feature_value)) not like '%N%' and
            upper(trim(feature_value)) not like '%O%' and
            upper(trim(feature_value)) not like '%P%' and
            upper(trim(feature_value)) not like '%Q%' and
            upper(trim(feature_value)) not like '%R%' and
            upper(trim(feature_value)) not like '%S%' and
            upper(trim(feature_value)) not like '%T%' and
            upper(trim(feature_value)) not like '%U%' and
            upper(trim(feature_value)) not like '%V%' and
            upper(trim(feature_value)) not like '%W%' and
            upper(trim(feature_value)) not like '%X%' and
            upper(trim(feature_value)) not like '%Y%' and
            upper(trim(feature_value)) not like '%Z%' and       
            upper(trim(feature_value)) <>'' and
            upper(trim(feature_value)) not like '%+%' and 
            upper(trim(feature_value)) is not null and
            --upper(trim(feature_value))<>'-' and 
            upper(trim(feature_value))<>'NULL' and 
            upper(trim(feature_value)) not like '%/%' and 
            upper(trim(feature_value)) not like '%-%' and 
            upper(trim(feature_value)) not like '%:%' and 
            feature_value is not null 
                then 'NUMERIC'           
            else 'STRING'
        end as value_type

Answer 1

您可以嘗試在LIKE語句中使用字符范圍來控制CASE噩夢：

CASE WHEN upper(trim(feature_value)) NOT LIKE '%[A-Z/-+:]%'
    AND upper(trim(feature_value)) NOT LIKE ''
    AND upper(trim(feature_value)) IS NOT NULL
    THEN 'NUMERIC'
    ELSE 'STRING'
END AS value_type

根據需要修改/擴展。