SQL Fiddle sau tạo ra một đầu ra như được hiển thị bên dưới:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 45
Server version: 5.5.35-1
Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> use test;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select `id` from `tablename`;
+-------------------+
| id |
+-------------------+
| 11829806563853313 |
| 11829806563853314 |
| 11829806563853315 |
| 11829806563853316 |
| 11829806563853317 |
| 11829806563853318 |
| 11829806563853319 |
| 11829806563853320 |
| 11829806563853321 |
| 11829806563853322 |
| 11829806563853323 |
| 11829806563853324 |
| 11829806563853325 |
| 11829806563853326 |
| 11829806563853327 |
| 11829806563853328 |
| 11829806563853329 |
| 11829806563853330 |
| 11829806563853331 |
| 11829806563853332 |
| 11829806563853333 |
| 11829806563853334 |
| 11829806563853335 |
| 11829806563853336 |
| 11829806563853337 |
| 11829806563853338 |
| 11829806563853339 |
| 11829806563853340 |
| 11829806563853341 |
| 11829806563853342 |
| 11829806563853343 |
| 11829806563853344 |
| 11829806563853345 |
| 11829806563853346 |
| 11829806563853347 |
| 11829806563853348 |
| 11829806563853349 |
| 11829806563853350 |
| 11829806563853351 |
| 11829806563853352 |
+-------------------+
40 rows in set (0.01 sec)
Chấp nhận câu trả lời nếu nó thực sự giải quyết được nhu cầu của bạn.
CẬP NHẬT
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 46
Server version: 5.5.35-1
Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> use test;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> DELIMITER //
mysql> DROP FUNCTION IF EXISTS `nextval`//
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> DROP TRIGGER IF EXISTS `shard_insert`//
Query OK, 0 rows affected (0.00 sec)
mysql> DROP TABLE IF EXISTS `tablename_seq`, `tablename`;
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE TABLE `tablename_seq` (
-> `seq` BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY
-> )//
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE TABLE `tablename` (
-> `id` BIGINT UNSIGNED PRIMARY KEY
-> )//
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE FUNCTION `nextval`()
-> RETURNS BIGINT UNSIGNED
-> DETERMINISTIC
-> BEGIN
-> DECLARE `_last_insert_id` BIGINT UNSIGNED;
-> INSERT INTO `tablename_seq` VALUES (NULL);
-> SET `_last_insert_id` := LAST_INSERT_ID();
-> DELETE FROM `tablename_seq`
-> WHERE `seq` = `_last_insert_id`;
-> RETURN `_last_insert_id`;
-> END//
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE TRIGGER `shard_insert` BEFORE INSERT ON `tablename`
-> FOR EACH ROW
-> BEGIN
-> DECLARE `seq_id`, `now_millis` BIGINT UNSIGNED;
-> DECLARE `our_epoch` BIGINT UNSIGNED DEFAULT 1314220021721;
-> DECLARE `shard_id` INT UNSIGNED DEFAULT 1;
-> SET `now_millis` := `our_epoch` + UNIX_TIMESTAMP();
-> SET `seq_id` := `nextval`();
-> SET NEW.`id` := (SELECT (`now_millis` - `our_epoch`) << 23 |
-> `shard_id` << 10 |
-> MOD(`seq_id`, 1024)
-> );
-> END//
Query OK, 0 rows affected (0.00 sec)
mysql> INSERT INTO `tablename`
-> VALUES
-> (0), (0), (0), (0), (0),
-> (0), (0), (0), (0), (0),
-> (0), (0), (0), (0), (0),
-> (0), (0), (0), (0), (0),
-> (0), (0), (0), (0), (0),
-> (0), (0), (0), (0), (0),
-> (0), (0), (0), (0), (0),
-> (0), (0), (0), (0), (0)//
Query OK, 40 rows affected (0.00 sec)
Records: 40 Duplicates: 0 Warnings: 0
mysql> DELIMITER ;
mysql> SELECT `id` FROM `tablename`;
+-------------------+
| id |
+-------------------+
| 12581084357198849 |
| 12581084357198850 |
| 12581084357198851 |
| 12581084357198852 |
| 12581084357198853 |
| 12581084357198854 |
| 12581084357198855 |
| 12581084357198856 |
| 12581084357198857 |
| 12581084357198858 |
| 12581084357198859 |
| 12581084357198860 |
| 12581084357198861 |
| 12581084357198862 |
| 12581084357198863 |
| 12581084357198864 |
| 12581084357198865 |
| 12581084357198866 |
| 12581084357198867 |
| 12581084357198868 |
| 12581084357198869 |
| 12581084357198870 |
| 12581084357198871 |
| 12581084357198872 |
| 12581084357198873 |
| 12581084357198874 |
| 12581084357198875 |
| 12581084357198876 |
| 12581084357198877 |
| 12581084357198878 |
| 12581084357198879 |
| 12581084357198880 |
| 12581084357198881 |
| 12581084357198882 |
| 12581084357198883 |
| 12581084357198884 |
| 12581084357198885 |
| 12581084357198886 |
| 12581084357198887 |
| 12581084357198888 |
+-------------------+
40 rows in set (0.00 sec)
Xem db-fiddle .
