Two ways to deal with conflicting data in MySQL and PG Libraries

mysql Processing mode

1.IGNORE 

When using INSERT Statement adds some row data to the table and an error occurs during processing ,INSERT The statement will be aborted , And return an error message . therefore , No rows may be inserted into the table .
however , If you use INSERT INGORE sentence , The line that caused the error is ignored , And insert the remaining rows into the table .

insert IGNORE into table(xxx,xxx) VALUES (xxx,xxx);

insert IGNORE into `test` (`id`,`name`,`times`,`add_time`)
VALUES
('1','woq','3','1529304418'),
('2','woa','4','1529304452'),
('3','woz','5','1529304425'),
('4','wow','6','1529304445');

remarks ：IGNORE  When , If the data in the original result set is repeated, an error will be reported ,REPLACE The method will not report an error
2.REPLACE INTO

If you find that this row of data already exists in the table （ Based on the primary key or unique index ） Then delete this row of data first , Then insert the new data .
otherwise , Insert new data directly .
It should be noted that ： The table that inserts data must have a primary key or a unique index ！ Otherwise ,replace into Will insert data directly , This will result in duplicate data in the table . 

REPLACE INTO table (xxx,xxx) VALUES (xxx,xxx);
REPLACE into `test` (`id`,`name`,`times`,`add_time`)
VALUES
('1','woq','3','1529304418'),
('2','woa','4','1529304452'),
('3','woz','5','1529304425'),
('4','wow','6','1529304445');

pg Library processing method

1. In case of conflicting data, do nothing

INSERT INTO customers (name, email)
VALUES
 (
 'Microsoft',
 '[email protected]'
 ) 
ON CONFLICT (name) 
DO NOTHING;
2. Conflicting data update operation encountered

INSERT INTO customers (name, email)
VALUES
 (
 'Microsoft',
 '[email protected]'
 ) 
ON CONFLICT (name) 
DO
 UPDATE
   SET email = EXCLUDED.email;
remarks ：DO NOTHING When , If there is duplicate data in the original result set, no error will be reported ,DO UPDATE When , If there is duplicate data in the original result set, an error will be reported