為什么我在 mysql 的這個查詢中出現語法錯誤

Question

DB 新手，我正在編寫查詢，但需要幫助來找出語法錯誤。 詢問：

SELECT IF (EXISTS(SELECT * FROM contact_address WHERE ad_ct_id = 1)) THEN
BEGIN
UPDATE contact_address set ad_city = 'Iraq'
END
ELSE
BEGIN
INSERT INTO contact_address (ad_ct_id, ad_type, ad_city)
VALUES (1, 'o', 'Iraq')
END
END IF;

錯誤：

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') THEN
BEGIN
UPDATE contact_address set ad_city = 'Iraq'
END
ELSE
BEGIN
INSERT I' at line 1

謝謝

Answer 1

刪除SELECT 。

IF (EXISTS(SELECT * FROM contact_address WHERE ad_ct_id = 1)) THEN
BEGIN
    UPDATE contact_address set ad_city = 'Iraq'
END
ELSE
BEGIN
    INSERT INTO contact_address (ad_ct_id, ad_type, ad_city)
    VALUES (1, 'o', 'Iraq')
END
END IF;

Answer 2

'為什么我會收到語法錯誤' - 你不能使用 if..end if outwith 存儲程序，mysql 不需要 begin..end 內 if..end if，if 語法應該是 if exists(select..)，每個語句都需要終止。