Question

我想插入一个新数据，但我想在查询中放入一个条件，如果有数据存在，则不会插入，如果不存在则可以插入。

INSERT INTO user_permission_index (guid, code, name,description, perm_type, time_create)   
VALUES 
(uuid_generate_v1(),'perm_trading_cashsale_by_branch','label_CanissueCashsaleByBranch','','acc_branch_index','0001-01-01') 
WHERE NOT EXISTS (SELECT * 
                  FROM user_permission_index 
                  WHERE code = 'perm_trading_cashsale_by_branch' 
                    AND name = 'label_CanissueCashsaleByBranch');

我在WHERE NOT时遇到语法错误。你们能帮助我吗？感谢。

Answer 1

您需要使用SELECT代替VALUES

INSERT INTO user_permission_index (guid, code, name,description, perm_type, time_create)   
select uuid_generate_v1(),
       'perm_trading_cashsale_by_branch',
       'label_CanissueCashsaleByBranch',
       '',
       'acc_branch_index',
       '0001-01-01' 
WHERE NOT EXISTS (SELECT * 
                  FROM user_permission_index 
                  WHERE code = 'perm_trading_cashsale_by_branch' 
                    AND name = 'label_CanissueCashsaleByBranch');

（我假设你是PostgreSQL，因为uuid_generate_v1()函数）

如果您正在使用“更新或插入”功能，可能需要查看以下内容：Insert, on duplicate update in PostgreSQL?

Answer 2

您需要将内部选择链接到外部插入语句

INSERT INTO user_permission_index upi (guid, code, name,description, perm_type, time_create) 
SELECT (uuid_generate_v1(),'perm_trading_cashsale_by_branch','label_CanissueCashsaleByBranch','','acc_branch_index','0001-01-01') 
WHERE NOT EXISTS (
SELECT * 
FROM user_permission_index 
WHERE code = 'perm_trading_cashsale_by_branch' 
  AND name = 'label_CanissueCashsaleByBranch'
      AND id = upi.id
);

但我认为说

会更好

INSERT INTO user_permission_index (guid, code, name,description, perm_type, time_create) 
SELECT (uuid_generate_v1(),'perm_trading_cashsale_by_branch','label_CanissueCashsaleByBranch','','acc_branch_index','0001-01-01') 
WHERE nvl(code, '') <> 'perm_trading_cashsale_by_branch'
   OR nvl(name, '') <> 'label_CanissueCashsaleByBranch';

如何在使用INSERT INTO时过滤重复项

2 个答案: