POSTGRESQL与MYSQL实现分割字符串的方法对比

实现分割字符串。 DELIMITER $$ CREATE DEFINER=`root`@`%` FUNCTION `func_get_split_string_total`( f_string VARCHAR(1000),f_delimiter VARCHAR(5) ) RETURNS INT(11) BEGIN -- Get the total number of given string. RETURN 1+(LENGTH(f_string) - LENG

实现分割字符串。
DELIMITER $$ CREATE DEFINER=`root`@`%` FUNCTION `func_get_split_string_total`( f_string VARCHAR(1000),f_delimiter VARCHAR(5) ) RETURNS INT(11) BEGIN -- Get the total number of given string. RETURN 1+(LENGTH(f_string) - LENGTH(REPLACE(f_string,f_delimiter,''))); END$$ DELIMITER ;

DELIMITER $$ CREATE DEFINER=`root`@`%` FUNCTION `func_get_split_string`( f_string VARCHAR(1000),f_delimiter VARCHAR(5),f_order INT) RETURNS VARCHAR(255) CHARSET utf8 BEGIN -- Get the separated number of given string. DECLARE result VARCHAR(255) DEFAULT ''; SET result = REVERSE(SUBSTRING_INDEX(REVERSE(SUBSTRING_INDEX(f_string,f_delimiter,f_order)),f_delimiter,1)); RETURN result; END$$ DELIMITER ;

DELIMITER $$ CREATE PROCEDURE `sp_print_result`( IN f_string VARCHAR(1000),IN f_delimiter VARCHAR(5) ) BEGIN -- Get the separated string. DECLARE cnt INT DEFAULT 0; DECLARE i INT DEFAULT 0; SET cnt = func_get_split_string_total(f_string,f_delimiter); DROP TABLE IF EXISTS tmp_print; CREATE TEMPORARY TABLE tmp_print (v_text varchar(200) NOT NULL); WHILE i 
我们来执行： 
CALL sp_print_result('love,you,hate,number',',');
query result
v_text 
love 
you 
hate 
number 
create or replace function split_to_string( IN f_string text, IN f_delimiter varchar(10) ) returns setof text as $ytt$ declare cnt int; declare i int; declare v_result text; begin i := 1; cnt := length(f_string) - length(replace(f_string,f_delimiter,''))+1; while i 
t_girl=# SELECT ytt FROM regexp_split_to_table('love,you,hate,number', E',+') AS ytt; ytt -------- love you hate number (4 rows) t_girl=#

第三种，用自带的WITH 语法来实现。 

t_girl=# with recursive ytt(f1,f2) as (
values (0,' '::text) 
union all 
select f1+1,split_part('love,you,hate,number',',',f1+1) from ytt where f1 =1 and f1