How to convert time date into timestamp in oracle
Conversion method: 1. Use the to_char() function to output the time and date in the specified format. The result is a string, the syntax is "to_char(date,"conversion format")"; 2. Use to_date () function, syntax "to_date("time string","converted time and date format")".
The operating environment of this tutorial: Windows 7 system, Oracle 11g version, Dell G3 computer.
oracle time and date conversion into timestamp
In Oracle, there are two methods to convert time and date into timestamp:
to_char() function
to_date() function
##1. to_char()
Output the time and date in the specified format, and the result is a string, not a date type.to_char(日期,"转换格式" )
select to_char(sysdate, 'yyyy-mm-dd') from dual; select to_char(sysdate, 'yyyy/mm/dd') from dual; select to_char(sysdate, 'yyyymmdd') from dual; select to_char(sysdate, 'yyyymmdd hh24:mi:ss') from dual;
select to_char(sysdate,'yyyy') from dual; select to_char(sysdate,'mm') from dual; select to_char(sysdate,'hh24') from dual; select to_char(sysdate,'mi') from dual;
2, to_date()
Convert the string to the specified time and date formatto_date("时间字符串","转换的时间日期格式")
select to_date('20220103','yyyymmdd') from dual; select to_date('20220103','yyyy-mm-dd') from dual; select to_date('20220103','yyyy/mm/dd') from dual; select to_date('20220103','yyyy-mm-dd hh24:mi:ss') from dual;
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