MariaDB创建表在外键约束上引发错误

Question

[按照以下顺序运行以下SQL语句会导致引发以下错误，我不知道出了什么问题，在Google中搜索了一些查询，这些查询对我来说似乎都是一样的。当在MySQL Workbench服务器上执行时，它们工作正常，但是当我在MariaDb服务器上尝试时，它们却无法正常工作。

错误：

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ' CONSTRAINT `playerid` FOREIGN KEY (playerid) REFERENCES st_player (id) ON DELET' at line 1

SQL语句：

1. CREATE TABLE IF NOT EXISTS `st_player` (
   `id` VARCHAR(45) NOT NULL, 
   `playerName` VARCHAR(45) NOT NULL, 
   PRIMARY KEY (`id`), 
   UNIQUE KEY `id` (`id`)
   );

2. CREATE TABLE IF NOT EXISTS `st_statistic` (
   `criteria` VARCHAR(45) NOT NULL, 
   `subcriteria` VARCHAR(45) NOT NULL, 
   `playerid` VARCHAR(45) NOT NULL, 
   `displayname` VARCHAR(45) NULL,
   `amount` INT NULL, 
   PRIMARY KEY (`criteria`, `subcriteria`, `playerid`), 
   INDEX `playerid_idx` (`playerid` ASC) VISIBLE, 
   CONSTRAINT `playerid` 
       FOREIGN KEY (`playerid`) REFERENCES `st_player` (`id`) 
       ON DELETE CASCADE 
       ON UPDATE NO ACTION
   );

Answer 1

您可能正在运行不支持不可见索引功能的MySQL版本。无论如何，VISIBLE是默认行为，因此您可以将其从create table语句中删除。

此外，MySQL自动在外键列上创建索引；这意味着您实际上不需要显式声明该索引。因此，我建议只删除索引声明。

此代码运行正常：

CREATE TABLE IF NOT EXISTS st_player(
    id VARCHAR(45) NOT NULL,
    playerName VARCHAR(45) NOT NULL, 
    PRIMARY KEY (id)
    -- UNIQUE KEY id(id)
);

CREATE TABLE IF NOT EXISTS st_statistic(
    criteria VARCHAR(45) NOT NULL,
    subcriteria VARCHAR(45) NOT NULL,
    playerid VARCHAR(45) NOT NULL,
    displayname VARCHAR(45) NULL,
    amount INT NULL, 
    PRIMARY KEY (criteria,subcriteria,playerid), 
    -- INDEX playerid_idx(playerid ASC), -- unnecessary (but it it is OK if you uncomment it)
    CONSTRAINT playerid
        FOREIGN KEY (playerid) REFERENCES st_player(id) 
        ON DELETE CASCADE 
        ON UPDATE NO ACTION
);