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What is the format of the date column in the database?
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if the data is text in dd/mm/yy format and you want to produce text formatted as <br />
DD-MON-YYYY &nbsp;HH24:MM:SS <br />
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then try this...<br />
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select to_char(to_date(yourdate,'<wbr />dd/mm/rr')<wbr />,'DD-MON-Y<wbr />YYY &nbsp;HH24:MI:SS') from yourtable<br />
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note, &nbsp;I change MM to MI in your time portion to return minutes instead of months
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Are you trying to use Oracle with Crystal Reports?<br />
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mlmcc
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First what is the data type of the column that you are looking at? &nbsp;DATE or TIMESTAMP or VARCHAR or CHAR?<br />
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If DATE, then this is a pretty good explanation how the date is stored -&gt; <a href="http://www.ixora.com.au/notes/date_representation.htm" rel="ugc">http://www.ixora.com.au/notes/date_representation.htm</a>&nbsp; &nbsp;This is not version dependent. &nbsp;They have been store this way on every version that I have ever worked with.<br />
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As far as the string representation when selected out of the database, that is dependent on the setting of NLS_DATE_FORMAT (assuming DATE datatype). &nbsp;While you can change this on the database side, it is a client setting and is easily overridden with an ALTER SESSION or registry/environment setting, or a few other ways. &nbsp;You cannot rely on the client not changing the value of the date formats.<br />
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The only true way to control the format is to select the data with a TO_CHAR and force the format there. &nbsp;At that point it is a string when it gets to the client and the date formats no longer apply.
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Hi <br />
&nbsp;Currently existing database datetime format is showing as DD/MM/YY<br />
How should we change the datetime format to &nbsp;DD-MON-YYYY &nbsp;HH24:MM:SS in oracle 12c<br />
for all tables existing in the database <br />
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Thanks
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Hi 
 Currently existing database datetime format is showing as DD/MM/YY
How should we change the datetime format to  DD-MON-YYYY  HH24:MM:SS in oracle 12c
for all tables existing in the database 


Thanks

how to update the datetime format in oracle 12c

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