Error Code Reference

Understanding HTTP 200 OK status code - the standard success response for HTTP requests indicating the request was fulfilled.

Understanding HTTP 201 Created status code - indicates a new resource has been successfully created as a result of the request.

Understanding HTTP 204 No Content status code - the request succeeded but the server has no content to return in the response body.

Understanding HTTP 301 Moved Permanently - the requested resource has been permanently moved to a new URL and all future requests should use the new URL.

Understanding HTTP 302 Found status code - the requested resource temporarily resides at a different URI. Future requests should still use the original URI.

Understanding HTTP 304 Not Modified - the resource has not been modified since the last request, so the cached version can be used.

Understanding HTTP 307 Temporary Redirect - the resource temporarily resides at a different URL and the request method must not be changed.

Understanding HTTP 308 Permanent Redirect - the resource has permanently moved to a new URL and the request method must not be changed.

Understanding HTTP 400 Bad Request - the server cannot process the request due to malformed syntax, invalid parameters, or other client errors.

Understanding HTTP 401 Unauthorized - the request requires authentication. The client must provide valid credentials to access the resource.

Understanding HTTP 403 Forbidden - the server understood the request but refuses to authorize it. Authentication will not help.

Understanding HTTP 404 Not Found - the server cannot find the requested resource. The URL may be incorrect or the resource may have been removed.

Understanding HTTP 405 Method Not Allowed - the HTTP method used is not supported for the requested resource.

Understanding HTTP 408 Request Timeout - the server timed out waiting for the client to send the complete request.

Understanding HTTP 409 Conflict - the request conflicts with the current state of the server, such as duplicate entries or version conflicts.

Understanding HTTP 413 Payload Too Large - the request body exceeds the maximum size the server is willing to process.

Understanding HTTP 415 Unsupported Media Type - the server refuses the request because the payload format is not supported.

Understanding HTTP 422 Unprocessable Entity - the server understands the request but cannot process it due to semantic errors in the content.

Understanding HTTP 429 Too Many Requests - the user has sent too many requests in a given time period (rate limiting).

Understanding HTTP 500 Internal Server Error - an unexpected condition was encountered on the server preventing it from fulfilling the request.

Understanding HTTP 501 Not Implemented - the server does not support the functionality required to fulfill the request.

Understanding HTTP 502 Bad Gateway - the server acting as a gateway received an invalid response from the upstream server.

Understanding HTTP 503 Service Unavailable - the server is temporarily unable to handle the request due to overload or maintenance.

Understanding HTTP 504 Gateway Timeout - the server acting as a gateway did not receive a timely response from the upstream server.

Understanding Linux exit code 0 - the command or program completed successfully without errors.

Understanding Linux exit code 1 - a general catchall error indicating the command failed for an unspecified reason.

Understanding Linux exit code 126 - the command was found but could not be executed, usually due to permission issues.

Understanding Linux exit code 127 - the command could not be found in the system PATH or specified location.

Understanding Linux exit code 128 - indicates an invalid argument was passed to the exit command, or serves as a base for signal-based exit codes.

Understanding Linux exit code 130 - the process was terminated by SIGINT, typically by pressing Ctrl+C.

Understanding Linux exit code 137 - the process was forcefully killed by SIGKILL, often due to out-of-memory (OOM) conditions.

Understanding Linux exit code 139 - the process was terminated due to a segmentation fault, caused by invalid memory access.

Understanding Linux exit code 143 - the process was terminated by SIGTERM, the standard graceful shutdown signal.

Understanding Linux exit code 2 - indicates misuse of a shell built-in command, such as incorrect syntax or invalid arguments.

Understanding Docker exit code 0 - the container's main process completed successfully and exited normally.

Understanding Docker exit code 1 - the container's main process failed with a general error, such as an application crash or runtime exception.

Understanding Docker exit code 125 - the Docker daemon encountered an error before the container process could start.

Understanding Docker exit code 126 - the container's entrypoint or command was found but could not be executed.

Understanding Docker exit code 127 - the container's entrypoint or command could not be found in the container's filesystem.

Understanding Docker exit code 137 - the container was forcefully killed, usually due to exceeding memory limits or by docker stop timeout.

Understanding Docker exit code 139 - the container process crashed with a segmentation fault due to invalid memory access.

Understanding Docker exit code 143 - the container received SIGTERM and terminated gracefully, typically from docker stop.

Understanding Docker exit code 255 - an unknown or unspecified error occurred in the container, often related to SSH or runtime failures.

Understanding MySQL error 1045 - access denied for the specified user. Authentication failed due to wrong credentials or missing privileges.

Understanding MySQL error 1049 - the specified database does not exist on the MySQL server.

Understanding MySQL error 1062 - a duplicate entry was found for a unique key constraint, preventing the insert or update.

Understanding MySQL error 1146 - the referenced table does not exist in the specified database.

Understanding MySQL error 1215 - cannot add a foreign key constraint due to data type mismatch, missing index, or engine incompatibility.

Understanding MySQL error 1451 - cannot delete or update a parent row because a foreign key constraint fails.

Understanding MySQL error 2002 - can't connect to the local MySQL server through the socket file. The server may not be running.

Understanding MySQL error 2003 - cannot connect to the MySQL server via TCP/IP. The server may be down, unreachable, or the port may be blocked.

Understanding PostgreSQL error 23503 foreign_key_violation - an insert or update violates a foreign key constraint.

Understanding PostgreSQL error 23505 unique_violation - a duplicate value violates a unique constraint on the table.

Understanding PostgreSQL error 28P01 invalid_password - authentication failed due to incorrect password for the specified user.

Understanding PostgreSQL error 42601 syntax_error - the SQL query contains a syntax error that prevents it from being parsed.

Understanding PostgreSQL error 42P01 undefined_table - the referenced table or view does not exist in the database.

Understanding Python AttributeError - raised when you try to access an attribute or method that doesn't exist on an object.

Understanding Python FileNotFoundError - raised when trying to open or access a file that does not exist at the specified path.

Understanding Python ImportError - raised when an import statement fails to find the module or cannot load a specific name from a module.

Understanding Python IndexError - raised when a sequence index is out of range, such as accessing a list element that doesn't exist.

Understanding Python KeyError - raised when a dictionary key is not found in the dictionary.

Understanding Python ModuleNotFoundError - raised when Python cannot find the module you are trying to import.

Understanding Python PermissionError - raised when trying to perform an operation without adequate access permissions.

Understanding Python RecursionError - raised when the maximum recursion depth is exceeded, usually indicating infinite recursion.

Understanding Python TypeError - raised when an operation or function is applied to an object of inappropriate type.

Understanding Python ValueError - raised when a function receives an argument of the right type but inappropriate value.

Understanding Node.js EACCES error - permission denied when accessing a file, directory, or port.

Understanding Node.js EADDRINUSE error - the port is already in use by another process, preventing the server from starting.

Understanding Node.js ECONNREFUSED error - the connection attempt was refused because the target server is not accepting connections.

Understanding Node.js ENOENT error - no such file or directory. The specified file or directory path does not exist.

Understanding Node.js EPERM error - operation not permitted. The operating system denied the requested operation.

Understanding Node.js ERR_HTTP_HEADERS_SENT - cannot set or send headers after they have already been sent to the client.

Understanding Node.js ERR_MODULE_NOT_FOUND - the specified ES module could not be found or resolved by the module loader.

Understanding Node.js ETIMEDOUT error - the connection attempt timed out before a response was received from the server.

Understanding AWS AccessDenied error - the IAM user or role does not have permission to perform the requested action on the resource.

Understanding AWS InvalidParameterValue error - a parameter value provided in the API request is not valid for the given context.