Oracle - Errores y soluciones
ORA-01422: exact fetch returns more than requested number of rows
Cause: The number specified in exact fetch is less than the rows returned.
Action: Rewrite the query or change number of rows requested.
ORA-06502: PL/SQL: numeric or value errorstring
Cause: An arithmetic, numeric, string, conversion, or constraint error occurred. For example, this error occurs if an attempt is made to assign the value NULL to a variable declared NOT NULL, or if an attempt is made to assign an integer larger than 99 to a variable declared NUMBER(2).
Action: Change the data, how it is manipulated, or how it is declared so that values do not violate constraints.
ORA-01031: insufficient privileges
Cause: An attempt was made to change the current username or password without the appropriate privilege. This error also occurs if attempting to install a database without the necessary operating system privileges. When Trusted Oracle is configure in DBMS MAC, this error may occur if the user was granted the necessary privilege at a higher label than the current login.
Action: Ask the database administrator to perform the operation or grant the required privileges. For Trusted Oracle users getting this error although granted the the appropriate privilege at a higher label, ask the database administrator to regrant the privilege at the appropriate label.
ORA-00020: maximum number of processes (string) exceeded
Cause: All process state objects are in use.
Action: Increase the value of the PROCESSES initialization parameter.
ORA-00021: session attached to some other process; cannot switch session
Cause: The user session is currently used by others.
Action: Do not switch to a session attached to some other process.
ORA-00022: invalid session ID; access denied
Cause: Either the session specified does not exist or the caller does not have the privilege to access it.
Action: Specify a valid session ID that you have privilege to access, that is either you own it or you have the CHANGE_USER privilege.