老是忘记的Oracel sql statements

-- find oracle version
SELECT * FROM SYS.product_component_version;

-- find table meta data: table name is in upper case
select * from all_tables WHERE TABLE_NAME = 'CUSTOMERS';

-- find constraint's attribute, like the table name it belongs to
select * from all_constraints WHERE CONSTRAINT_NAME = 'SYS_C0010167';

-- unlock Oracle account: e.g. "REPORTS" locked, to unlock it
alter user REPORTS identified by PASSWORD account unlock;

-- oracle date function: turn a date string to oracle DATE
SELECT to_date('2011-07-29 16:6:39','yyyy-mm-dd hh24:mi:ss') FROM DUAL;

-- convert miliseconds (long/number) to date string
select to_char( (to_date('01-JAN-1970','DD-MON-YYYY') + (1323820061893/1000 / (60 * 60 * 24) )), 'YYYY-MON-DD HH24:MI:SS') "seconds to date" from sys.dual;

SELECT SYSDATE FROM DUAL;
SELECT CURRENT_DATE FROM DUAL;
SELECT CURRENT_TIMESTAMP FROM DUAL;

-- 奥若靠萨客死！