Concatenate multiple rows in the same column of Oracle into a string using SQL.

Concatenate multiple rows of records in the same column in Oracle into a string [SQL] -- raw data -- a 111 -- B 222 -- a 333 -- a 444 -- B 555 -- final result -- a 111*333*444 SELECT L4.L _ TIME, MAX (SUBSTR (L4. group CONTENT, 2) final field value FROM (SELECT L3.L _ TIME, SYS_CONNECT_BY_PATH (L3.L _ CONTENT ,'*') AS group content from (SELECT L2.L _ TIME, L2.L _ CONTENT, L2.L _ TIME | L2. group id as group field plus number, l2.L _ TIME | (L2. group ID-1) AS upper-level group field plus number FROM (SELECT L1.L _ TIME -- group basis, l1.L _ CONTENT -- the values of different rows to be merged in the same column. The value is from logs L1 in the ROW_NUMBER () OVER (partition by L1.L _ time order by L1.L _ content asc) group) l2) L3 start with L3. The upper-level grouping field is numbered LIKE '% 0' connect by prior L3. The grouping field is numbered = L3. The upper-level grouping field is numbered) l4 WHERE L_TIME = '000000' group by L4.L _ TIME -- ROW_NUMBER () OVER (partition by a order by B desc) new column name -- group by a and sort by B within the GROUP, the value calculated by this function indicates the sequential number after sorting in each group (the sequential and unique in the group) -- SYS_CONNECT_BY_PATH function: the first parameter is a field in the form of a tree, the second parameter is the delimiter used to separate the parent and its child. -- connect by prior indicates the parent-child relationship. -- start with indicates the node that you want to START traversing.: drop table logs; create table logs (L_ID VARCHAR2 (32) not null, L_CONTENT VARCHAR2 (512), L_TIME VARCHAR2 (32), L_USER VARCHAR2 (32 ), primary key (L_ID); comment on table logs is 'Log table'; comment on column logs. rochelle id is 'Log id'; comment on column logs. rochelle content IS 'Log content'; comment on column logs. rochelle time IS 'time'; comment on column logs. rochelle user IS 'operator '; insert into logs (L_ID, L_CONTENT, L_TIME, L_USER) VALUES ('123456', 'black', '123456', '1234568 '); insert into logs (L_ID, L_CONTENT, L_TIME, L_USER) VALUES ('000000', 'white', '000000', '000000'); insert into logs (L_ID, L_CONTENT, rochelle time, Rochelle user) VALUES ('123', 'black and white ', '123', '123'); insert into logs (Rochelle ID, Rochelle content, L_TIME, Rochelle user) VALUES ('20140901', 'White la', '20160901', '20160901'); insert into logs (L_ID, L_CONTENT, L_TIME, L_USER) VALUES ('20160301 ', 'Hey, ', '123', '123 ');