Sql change the result length or time format

Question

My database is Oracle, and I use navicat to query data.

My code is below:

select 

        jzmktr.VPRONAME as jzmktrvproname, 
        jzbid.vproname as jzbidvproname,
        jzbid.vprolocus as jzbidvprolocus,
        jzcur.vname as jzcurvname,
        doc.name as docname,
        zspm.def2 as zspmdef2,
        oa.name as oaname,
        zspm.def6 as zspmdef6,
        zspm.def4 as zspmdef4,
        zpus.def3 as zpusdef3,
        jzbidt.dstartdate as jzbidtdstartdate,
        jzbidt.dcompletedate as jzbidtdconpletedate,
                zspm.def4 as zspmdef4,
        jzcur.PK_GROUP

from JZMKT_REGISTER jzmktr 
left join  JZCU_REGISTER jzcur
on jzcur.PK_REGISTER = jzmktr.pk_customer
left join JZBID_VENDSTART jzbid
on jzmktr.PK_MKTREGISTER = jzbid.PK_MKTREGISTER
left join jzbid_hitbidlog hit 
on hit.pk_vendstart = jzbid.pk_vendstart
left join ZSPM_MAK_EXPLANATION zspm
on zspm.def16 = hit.pk_hitbidlog
left join zspm_pub_uf_singlehead_h zpus 
on zpus.def1 = jzmktr.PK_MKTREGISTER
left join JZBID_TENDERCHK jzbidt 
on jzbidt.pk_vendstart = jzbid.pk_vendstart 
left join bd_defdoc doc 
on doc.pk_defdoc = jzbid.pk_operatetype
left join org_adminorg oa 
on oa.pk_adminorg = zspm.def5
where jzmktr.dr='0' and jzmktr.FSTATUSFLAG='1'

You can see the snapshot, this is the sql execute result, the time format of jzbidtdstartdate and jzbidtdconpletedate is yyyy-MM-dd HH:mm:ss :

How can I set the time format to yyyy-MM-dd ?

---

EDIT

If I change the jzbidtdstartdate to :

to_char(jzbidt.dstartdate,  'yyyy-MM-dd') as jzbidtdstartdate,

I will get this error:

on doc.pk_defdoc = jzbid.pk_operatetype  
left join org_adminorg oa   
on oa.pk_adminorg = zspm.def5  
where jzmktr.dr='0' and jzmktr.FSTATUSFLAG='1'  
--and jzmktr.pk_org in (parameter('param3'))  
  --       and substr(jzmktr.dbilldate,1,10)>=parameter('param1')  
    --     and substr(jzmktr.dbilldate,1,10)<=parameter('param2')  
[Err] ORA-01722: invalid number  

---

UPDATE

I search the jzbidt.dstartdate in the database, it is CHAR type.

Answer 1

In your SQL select clause, change the column from jzbidt.dstartdate to to_char(jzbidt.dstartdate, 'YYYY-MM-DD') to get the date in your required format, assuming it is of a date type.

Since it is of char type, you only need to do a substring, so substr(jzbidt.dstartdate, 0,10) will work fine.

Answer 2

如果jzbidt.dstartdate是CHAR ，则应将char转换为date ，然后格式化日期：

to_char(to_date(jzbidt.dstartdate, 'yyyy-MM-dd hh24:mi:ss'), 'yyyy-MM-dd'),