H2數據庫CREATE TABLE有約束

Question

我有兩個SQL語句：

CREATE TABLE legs(legid INT PRIMARY KEY AUTO_INCREMENT NOT NULL,
                  playerid1 INT NOT NULL REFERENCES players(playerid),
                  playerid2 INT NOT NULL REFERENCES players(playerid),
                  added TIMESTAMP AS CURRENT_TIMESTAMP NOT NULL);

ALTER TABLE legs ADD CONSTRAINT distinct_players CHECK(playerid1 <> playerid2);

我99％肯定我應該能夠將它們壓縮成一個，即：

CREATE TABLE table(...
                   playerid2 INT NOT NULL REFERENCES players(playerid) CHECK(playerid1 <> playerid2),
                   ...);

但是，我一直收到語法錯誤。 AFAIK，這是約束的所在。

Answer 1

CREATE TABLE legs(legid INT PRIMARY KEY AUTO_INCREMENT NOT NULL,
                  playerid1 INT NOT NULL REFERENCES players(playerid),
                  playerid2 INT NOT NULL REFERENCES players(playerid),
                  added TIMESTAMP AS CURRENT_TIMESTAMP NOT NULL,
                  CHECK (playerid1 <> playerid2));