Error

SELECT CASE WHEN  null  =  null  THEN NULL ELSE cast( null  AS numeric) END 

No error

DO
$$
DECLARE
   power text :=  null ;
BEGIN
   PERFORM CASE WHEN power =  null  THEN null ELSE cast(power AS numeric) END;
END
$$

Explanation

如果你进行问询,即使有<条码>的表述也会产生例外情况,即使有<条码>。 ELSE 从未执行过,因为它是invalid content syntax,而这一例外是在 s(如错误信息所暗示的)期间而不是在执行期间提出的。

缩略语 字面上的二例在组别后与初审无关。

为了像这样充满活力,你需要检查一下之前的数值,然后才能建立查询卡。 或您使用职能或准备的声明,并将价值作为<>参数。 这也会奏效。

More advice after comment:

在你的特殊情况下,你可以检查 app具的价值,并打造这样的 que:

INSERT INTO tbl(name, abc_id, created, power) 
SELECT  xyz 
     , abc_id
     , now()
     , <insert_value_of_power_or_NULL_here> -- automatically converted to numeric
FROM   abc;

You may be interested in a different approach to INSERT data from a file conditionally.
Use COPY for files local to the server or psql s meta-command copy for files local to the client.

if the field value is null, and you want in this case to map it to some value you can use coalesce(field_name, Some value ) or coalesce(field_name, 123).
For full documentation see here.

您必须同国际不动产业者进行核对,而不是在你处理国际不动产业联合会时做到:

INSERT into someTable(name,created,power) 
SELECT  xyz ,now(),
case when :power IS null then NULL else cast(:power as numeric) end from abc 

INSERT into someTable(name,created,power) SELECT  xyz ,now(),
   case :power when  null  then NULL else :power end::numeric from abc

I was trying to do something similar in order to update/insert some records where a numeric value can be null or not. You can validate a variable before you send it to the function or inside the function depending the value passed (For me using a variable is better than use CASE WHEN THEN ELSE END CASE every time you need to validate the value)

因此,与民族解放军的价值观合作,利用定期比较操作,以便找到更新的记录,可以通过向全国人民代表大会转变_null_ Equals来实现。

我希望这能帮助一个人

CREATE OR REPLACE FUNCTION update_insert_transaction(vcodaccount integer, vcodaccountaux text, 
  vdescription text, vcodgroup integer)
  RETURNS integer AS $$
DECLARE
  n integer = 0;
  vsql text =  NULL ; 
BEGIN 
    IF vcodaccountaux <>    THEN
        vsql = vcodaccountaux;
    END IF; 
        SET LOCAL transform_null_equals TO ON;
        EXECUTE  UPDATE account_import_conf SET (codaccount, codaccountaux, description, codgroup) = 
            ( ||vcodaccount|| , ||vsql|| ,trim( ||quote_literal(vdescription)|| ), ||vcodgroup|| ) 
            WHERE codaccount= ||vcodaccount||  AND codaccountaux =  ||vsql||  RETURNING *  ;
    GET DIAGNOSTICS n = ROW_COUNT;
    IF n = 0 THEN
    EXECUTE  INSERT INTO account_import_conf (codaccount, codaccountaux, description, codgroup)         
        SELECT  ||vcodaccount|| , ||vsql||  ,trim( ||quote_literal(vdescription)|| ), ||vcodgroup|| ; ;
    END IF;
RETURN n;
END;$$
  LANGUAGE plpgsql;