How to split varchar column in Oracle in three columns
我有一个可以容纳 120 个字符的地址字段,需要将它分成三个不同的列,每列 40 个字符长。
示例:
1 2 3 | Table name: Address Column name: Street_Address Select Street_Address * from Address |
输出:
我需要把这个地址拆分成
和
所有三个地址都是
所以结果应该是这样的:
1 2 3 4 5 6 7 8 | Address_1 152 Main st North Pole Factory 44, near Address_2 the rear entrance cross the street and Address_3 turn left and keep walking straight. |
请注意,每个地址字段最多可以占用 40 个字符,并且必须是整个单词,它不能被截断一半而没有意义。
我正在使用 oracle 11i 数据库。
您可以使用递归子查询分解(递归 CTE):
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | with s (street_address, line, part_address, remaining) as ( select street_address, 0 as line, null as part_address, street_address as remaining from address union all select street_address, line + 1 as line, case when length(remaining) <= 40 then remaining else substr(remaining, 1, instr(substr(remaining, 1, 40), ' ', -1, 1)) end as part_address, case when length(remaining) <= 40 then null else substr(remaining, instr(substr(remaining, 1, 40), ' ', -1, 1) + 1) end as remaining from s ) cycle remaining set is_cycle to 'Y' default 'N' select line, part_address from s where part_address is not null order by street_address, line; |
你的数据给出了:
1 2 3 4 5 | LINE PART_ADDRESS ---------- ---------------------------------------- 1 152 Main st North Pole Factory 44, near 2 the rear entrance cross the street and 3 turn left and keep walking straight. |
带有两个地址的 SQL Fiddle 演示。
您还可以将这些部分值转换为列,我认为这是您的最终目标,例如作为一个视图:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | create or replace view v_address as with cte (street_address, line, part_address, remaining) as ( select street_address, 0 as line, null as part_address, street_address as remaining from address union all select street_address, line + 1 as line, case when length(remaining) <= 40 then remaining else substr(remaining, 1, instr(substr(remaining, 1, 40), ' ', -1, 1)) end as part_address, case when length(remaining) <= 40 then null else substr(remaining, instr(substr(remaining, 1, 40), ' ', -1, 1) + 1) end as remaining from cte ) cycle remaining set is_cycle to 'Y' default 'N' select street_address, cast (max(case when line = 1 then part_address end) as varchar2(40)) as address_1, cast (max(case when line = 2 then part_address end) as varchar2(40)) as address_2, cast (max(case when line = 3 then part_address end) as varchar2(40)) as address_3 from cte where part_address is not null group by street_address; |
另一个 SQL 小提琴。
值得注意的是,如果
这相当"又快又脏",但我认为它给出了正确的结果。
我使用了流水线表,但可能没有它也可以完成...
这是一个 sqlfiddle 演示
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 | create table t1(id number, adr varchar2(120)) / insert into t1 values(1, '152 Main st North Pole Factory 44, near the rear entrance cross the street and turn left and keep walking straight.') / insert into t1 values(2, '122 Main st Pole Factory 44, near the rear entrance cross the street and turn left and keep walking straight. asdsa') / create or replace type t is object(id number, phrase1 varchar2(40), phrase2 varchar2(40), phrase3 varchar2(40)) / create or replace type t_tab as table of t / create or replace function split_string(id number, str in varchar2) return t_tab pipelined is v_token varchar2(40); v_token_i number := 0; v_cur_len number := 0; v_res_str varchar2(121) := str || ' '; v_p1 varchar2(40); v_p2 varchar2(40); v_p3 varchar2(40); v_p_i number := 1; begin v_token_i := instr(v_res_str, ' '); while v_token_i > 0 loop v_token := substr(v_res_str, 1, v_token_i - 1); if v_cur_len + length(v_token) < 40 then if v_p_i = 1 then v_p1 := v_p1 || ' ' || v_token; elsif v_p_i = 2 then v_p2 := v_p2 || ' ' || v_token; elsif v_p_i = 3 then v_p3 := v_p3 || ' ' || v_token; end if; v_cur_len := v_cur_len + length(v_token) +1; else v_p_i := v_p_i + 1; if v_p_i = 2 then v_p2 := v_p2 || ' ' || v_token; elsif v_p_i = 3 then v_p3 := v_p3 || ' ' || v_token; end if; v_cur_len := length(v_token); end if; v_res_str := substr(v_res_str, v_token_i + 1); v_token_i := instr(v_res_str, ' '); end loop; pipe row(t(id, v_p1, v_p2, v_p3)); return; end split_string; / |
然后查??询:
1 2 | select parts.*, length(PHRASE1), length(PHRASE2), length(PHRASE3) from t1, table(split_string(t1.id, t1.adr)) parts |