Database insert and update-query whether the primary key exists and insert statements are implemented using an SQL statement.

If you insert a record into the database, you always need to check whether the record exists. If it does not exist, you need to insert it. If it exists, you can give up or give a prompt,

 

Can we use a record?

 

I found the SQL usage of DB2 and Oracle:

 

DB2:

 

Merge into schema. table as t using table (values ('keyvalue') S (keyname) on (T. keyname = S. keyname) When not matched then insert (keyname, contentlname) values (?,?);

 

ORACLE:

 

Insert into schema. Table (keyname, contentlname) Select ?,? From dual where not exists (select * from Schema. Table where keyname = ?);

 

Preparestatement is used here.

Maybe you have used MySQL or sqlserver, and the idea is basically the same.

 

Valid coding can give you confidence, make you feel strong!