An error example of a connection string

A connection string. No problem. Running:

Starting from index 0, the format of the initialized string is invalid.

Later, I found that the problem occurred in one of my SQL statements:

String mysql = "select * from USER where USER_ID =" "UserID
"AND USER_PSW =" "UserPsw "";

System. Data. SqlClient. SqlException: syntax error near the keyword USER.

Later, it was found that a USER table was created in the database, and the USER is the SQL server built-in variable with the value of the username of the current connection, so it is not allowed, or it is best not to use the USER keyword. USER is NVARCHAR type.