Indexof/lastindexof and lpad in Oracle

Indexof/lastindexof and lpad in Oracle

-- In the indexof and lastindexof instr ('upgrade floor ', 'or', 3, 2) of PL/SQL, the source string is 'upgrade floor ', the target string is 'or', the start position is 3, and the position of the first matching item is obtained. -- The default search order is left to right. When the start position is negative, search from the right Select substr ('2. 3.30.41 ', instr ('1. 2.30.1', '.',-1, 1) + 1) from dual Indexof: The third parameter of substr is 1; Lastindexor: The third parameter of substr is-1. Application: Update subject t set T. subject_id_v = lpad (substr (T. subject_id, instr (T. subject_id ,'. ',-1, 1) + 1), 3, '0 ') Note: Take the string following the last "." In the subject_id field. If the length of the obtained string is less than 3, add 0 to the front of the string to supplement the three.