存储过程(在csv字符串varchar(1000)中)
csv字符串具有1,2,3,4,5,6
我希望将此csv字符串放入下表中
如果csv字符串是1,2,3,4,5,6,7,8然后
提前致谢
最佳答案
验证并根据需要进行调整:
mysql> SELECT VERSION();
+-----------+
| VERSION() |
+-----------+
| 5.7.18 |
+-----------+
1 row in set (0.00 sec)
mysql> DROP PROCEDURE IF EXISTS `insert_split`;
Query OK, 0 rows affected (0.00 sec)
mysql> DROP FUNCTION IF EXISTS `split_str`;
Query OK, 0 rows affected (0.00 sec)
mysql> DROP TABLE IF EXISTS `tbl`;
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE TABLE IF NOT EXISTS `tbl` (
-> `col1` VARCHAR(255),
-> `col2` VARCHAR(255)
-> );
Query OK, 0 rows affected (0.00 sec)
mysql> -- MySQL Split String Function by Federico Cargnelutti
mysql> -- http://blog.fedecarg.com/2009/02/22/mysql-split-string-function/
mysql> CREATE FUNCTION `split_str` (
-> `str` TEXT,
-> `delim` CHAR(1),
-> `item` INT UNSIGNED
-> ) RETURNS VARCHAR(255)
-> BEGIN
-> DECLARE `_current_str` TEXT DEFAULT SUBSTRING_INDEX(`str`, `delim`, `item`);
-> DECLARE `_prev_str` TEXT DEFAULT SUBSTRING_INDEX(`str`, `delim`, `item`-1);
-> IF `_current_str` = `_prev_str` THEN
-> RETURN NULL;
-> ELSE
-> RETURN REPLACE(
-> SUBSTRING(
-> `_current_str`,
-> CHAR_LENGTH(`_prev_str`) + 1
-> ),
-> `delim`, '');
-> END IF;
-> END//
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER //
mysql> CREATE PROCEDURE `insert_split`(`str` TEXT)
-> BEGIN
-> DECLARE `_delim` CHAR(1) DEFAULT ',';
-> DECLARE `_iteration` INT UNSIGNED DEFAULT 0;
-> DECLARE `_current_value` VARCHAR(255);
-> DECLARE `_odd_value` VARCHAR(255) DEFAULT '';
-> `repeat`: LOOP
-> SET `_iteration` := `_iteration` + 1;
-> SET `_current_value` := `split_str`(`str`, `_delim`, `_iteration`);
-> IF `_current_value` IS NULL THEN
-> LEAVE `repeat`;
-> END IF;
-> IF (`_iteration` MOD 2) = 0 THEN
-> INSERT INTO `tbl` (`col1`, `col2`)
-> VALUES (NULLIF(`_odd_value`, ''), NULLIF(`_current_value`, ''));
-> ELSE
-> SET `_odd_value` := `_current_value`;
-> END IF;
-> END LOOP `repeat`;
-> END//
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER ;
mysql> CALL `insert_split`('1,2,3,4,5,6');
Query OK, 1 row affected (0.00 sec)
mysql> SELECT `col1`, `col2`
-> FROM `tbl`;
+------+------+
| col1 | col2 |
+------+------+
| 1 | 2 |
| 3 | 4 |
| 5 | 6 |
+------+------+
3 rows in set (0.00 sec)
mysql> TRUNCATE TABLE `tbl`;
Query OK, 0 rows affected (0.00 sec)
mysql> CALL `insert_split`('1,2,3,4,5,6,7,8');
Query OK, 1 row affected (0.00 sec)
mysql> SELECT `col1`, `col2`
-> FROM `tbl`;
+------+------+
| col1 | col2 |
+------+------+
| 1 | 2 |
| 3 | 4 |
| 5 | 6 |
| 7 | 8 |
+------+------+
4 rows in set (0.00 sec)
请参见db-fiddle。
更新
如果您使用奇数值和偶数值,则可以使用以下内容:
mysql> SELECT VERSION();
+-----------+
| VERSION() |
+-----------+
| 5.7.18 |
+-----------+
1 row in set (0.00 sec)
mysql> DROP PROCEDURE IF EXISTS `insert_split`;
Query OK, 0 rows affected (0.00 sec)
mysql> DROP FUNCTION IF EXISTS `split_str`;
Query OK, 0 rows affected (0.00 sec)
mysql> DROP TABLE IF EXISTS `tbl`;
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE TABLE IF NOT EXISTS `tbl` (
-> `col1` VARCHAR(255),
-> `col2` VARCHAR(255)
-> );
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER //
mysql> -- MySQL Split String Function by Federico Cargnelutti
mysql> -- http://blog.fedecarg.com/2009/02/22/mysql-split-string-function/
mysql> CREATE FUNCTION `split_str` (
-> `str` TEXT,
-> `delim` CHAR(1),
-> `item` INT UNSIGNED,
-> `max_len_str` SMALLINT UNSIGNED
-> ) RETURNS VARCHAR(255)
-> BEGIN
-> DECLARE `_current_str` TEXT DEFAULT SUBSTRING_INDEX(`str`, `delim`, `item`);
-> DECLARE `_prev_str` TEXT DEFAULT SUBSTRING_INDEX(`str`, `delim`, `item`-1);
-> IF `_current_str` = `_prev_str` AND CHAR_LENGTH(`_prev_str`) = `max_len_str` THEN
-> RETURN NULL;
-> ELSE
-> RETURN REPLACE(
-> SUBSTRING(
-> `_current_str`,
-> CHAR_LENGTH(`_prev_str`) + 1
-> ),
-> `delim`, '');
-> END IF;
-> END//
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE PROCEDURE `insert_split`(`str` TEXT)
-> BEGIN
-> DECLARE `_max_length_str` SMALLINT UNSIGNED DEFAULT CHAR_LENGTH(`str`);
-> DECLARE `_delim` CHAR(1) DEFAULT ',';
-> DECLARE `_iteration` INT UNSIGNED DEFAULT 0;
-> DECLARE `_odd_value`, `_even_value` VARCHAR(255);
-> `repeat`: LOOP
-> SET `_odd_value` := `split_str`(`str`, `_delim`, `_iteration` + 1, `_max_length_str`);
-> SET `_even_value` := `split_str`(`str`, `_delim`, `_iteration` + 2, `_max_length_str`);
-> IF `_odd_value` IS NULL AND `_even_value` IS NULL THEN
-> LEAVE `repeat`;
-> END IF;
-> INSERT INTO `tbl` (`col1`, `col2`)
-> VALUES (NULLIF(`_odd_value`, ''), NULLIF(`_even_value`, ''));
-> SET `_iteration` := `_iteration` + 2;
-> END LOOP `repeat`;
-> END//
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER ;
mysql> TRUNCATE TABLE `tbl`;
Query OK, 0 rows affected (0.00 sec)
mysql> CALL `insert_split`('1,2,3,4,5,6');
Query OK, 1 row affected (0.00 sec)
mysql> SELECT `col1`, `col2`
-> FROM `tbl`;
+------+------+
| col1 | col2 |
+------+------+
| 1 | 2 |
| 3 | 4 |
| 5 | 6 |
+------+------+
3 rows in set (0.00 sec)
mysql> TRUNCATE TABLE `tbl`;
Query OK, 0 rows affected (0.00 sec)
mysql> CALL `insert_split`('1,2,3,4,5,6,7,8');
Query OK, 1 row affected (0.00 sec)
mysql> SELECT `col1`, `col2`
-> FROM `tbl`;
+------+------+
| col1 | col2 |
+------+------+
| 1 | 2 |
| 3 | 4 |
| 5 | 6 |
| 7 | 8 |
+------+------+
4 rows in set (0.00 sec)
mysql> TRUNCATE TABLE `tbl`;
Query OK, 0 rows affected (0.01 sec)
mysql> CALL `insert_split`(',,,');
Query OK, 1 row affected (0.00 sec)
mysql> SELECT `col1`, `col2`
-> FROM `tbl`;
+------+------+
| col1 | col2 |
+------+------+
| NULL | NULL |
| NULL | NULL |
+------+------+
2 rows in set (0.00 sec)
mysql> TRUNCATE TABLE `tbl`;
Query OK, 0 rows affected (0.00 sec)
mysql> CALL `insert_split`(',1,,,3');
Query OK, 1 row affected (0.00 sec)
mysql> SELECT `col1`, `col2`
-> FROM `tbl`;
+------+------+
| col1 | col2 |
+------+------+
| NULL | 1 |
| NULL | NULL |
| 3 | NULL |
+------+------+
3 rows in set (0.00 sec)
请参见db-fiddle。