ChuckBell
commented
5 years ago Catching up on some posts. Forgive me if I’ve asked this already, but what version of MySQL are you using?
This error manifests in two cases; a) when using a non-Oracle version of MySQL, or b) when not reading the data from a previous query before running another. In (b), make sure you also read the column data since that is sent over the wire first. Check out the sample sketches for how to do this properly.
That said, your sketch is using stored routines and if they are returning values or a result set, you must read that before executing the next query. Now, a challenge for you: write your SQL statements without the stored routines. IMHO, stored routines are short cuts and optimizations which can cause issues like this during development. I make it a point to avoid them until my code is working correctly - then I add the optimizations. ;)
On Feb 25, 2019, at 5:17 PM, xIceFox notifications@github.com wrote:
Hello, I do a project where I read RFID Card System to check how long people are on a event. My Arduino is the MySQL Client, which reads the RFID Cards and call procedures on the SQL Server. Im using the MySQL Connector to run stored Procedures in MySQL. At the End of the Procedure in MySQL I do:
Select "Successful" or when the Procedure crashes: Select "Error"
Now I want to read this with Basic Select.
The Problem is: The First time I do the Basic Select, it works fine. I get the Information of the Procedure instantly.
The Second Time I do the Basic Select, I get an empty Line back.
The Third Time I do the Basic Select, I get an Bad mojo. EOF found reading column header. ERROR: You must read the columns first!.
I can post my Serial Monitor here:
22:55:15.378 -> Connecting... 22:55:17.623 -> Connected to server version 8.0.14 22:59:30.872 -> Modus: Anmelden 22:59:32.067 -> Gelesene UID: 7A 2E 8C BB 22:59:32.615 -> call sas.Anmeldung('7A 2E 8C BB',1); 22:59:32.719 -> Successful 22:59:32.719 -> Anmeldung abgeschlossen :) 22:59:34.122 -> Gelesene UID: 7A 2E 8C BB 22:59:34.666 -> call sas.Anmeldung('7A 2E 8C BB',1); 22:59:35.555 -> 22:59:35.555 -> Anmeldung abgeschlossen :) 22:59:36.810 -> Gelesene UID: 7A 2E 8C BB 22:59:37.355 -> call sas.Anmeldung('7A 2E 8C BB',1); 22:59:37.390 -> Bad mojo. EOF found reading column header. 22:59:37.424 -> ERROR: You must read the columns first! 22:59:37.459 -> 22:59:37.459 -> Anmeldung abgeschlossen :)
I don't know why, but when I reset the Arduino, or I reconnect to the Server with the SoftReset, the first time it will work. The Problem is, that I haven't the time to soft reset my Arduino every time, because there are many people trying to get into this event.
My code is here:
`#include
include
include
include
include
define RST_PIN 5
define SS_PIN 53
IPAddress server_addr(I will hide this for security reasons :D); byte mac_addr[] = {I will hide this for security reasons :D }; char user[] = "I will hide this for security reasons :D"; char password[] = "I will hide this for security reasons :D";
EthernetClient client; MySQL_Connection conn((Client *)&client);
MFRC522 mfrc522(SS_PIN, RST_PIN);
int GID = 1; char query[128]; char SQLQueryAnmeldung[] = "call sas.Anmeldung('%s',%d);"; char SQLQueryAbmeldung[] = "call sas.Abmeldung('%s',%d);"; String Modus;
void setup() { pinMode(30, INPUT); pinMode(31, INPUT); pinMode(22, OUTPUT); pinMode(24, OUTPUT); pinMode(26, OUTPUT); Serial.begin(9600);
SPI.begin(); mfrc522.PCD_Init();
Ethernet.begin(mac_addr); Serial.println("Connecting..."); if (conn.connect(server_addr, 3306, user, password)) { delay(500); digitalWrite(26, LOW); digitalWrite(24, HIGH); digitalWrite(22, LOW); } else { Serial.println("Connection failed."); digitalWrite(26, HIGH); digitalWrite(24, LOW); digitalWrite(22, LOW); } }
void loop() {
if (mfrc522.PICC_IsNewCardPresent() && mfrc522.PICC_ReadCardSerial() ) { if (Modus == "Anmeldung") { SQLAnmeldung(ReadTag()); digitalWrite(26, LOW); digitalWrite(24, HIGH); digitalWrite(22, LOW); }
if (Modus == "Abmeldung") { SQLAbmeldung(ReadTag()); digitalWrite(26, LOW); digitalWrite(24, HIGH); digitalWrite(22, LOW); } }
if (digitalRead(30)) { Modus = "Anmeldung"; delay(1000); Serial.println("Modus: Anmelden"); } if (digitalRead(31)) { Modus = "Abmeldung"; delay(1000); Serial.println("Modus: Abmelden"); } }
void SQLAnmeldung(String RFID) { row_values row = NULL; String Res = ""; digitalWrite(26, HIGH); digitalWrite(24, LOW); digitalWrite(22, LOW); delay(500); sprintf(query, SQLQueryAnmeldung, RFID.c_str(), GID); Serial.println(query); MySQL_Cursor cur_mem = new MySQL_Cursor(&conn); cur_mem->execute(query); column_names *columns = cur_mem->get_columns();
do { row = cur_mem->get_next_row(); if (row != NULL) { Res = row->values[0]; } } while (row != NULL); delete cur_mem; Serial.println(Res); Serial.println("Anmeldung abgeschlossen :)"); delay(500);
}
void SQLAbmeldung(String RFID) { digitalWrite(26, HIGH); digitalWrite(24, LOW); digitalWrite(22, LOW); delay(500); sprintf(query, SQLQueryAbmeldung, RFID.c_str(), GID); MySQL_Cursor *cur_mem = new MySQL_Cursor(&conn); cur_mem->execute(query); delete cur_mem; Serial.println("Abmeldung abgeschlossen :)"); }
String ReadTag() { String UID; Serial.print("Gelesene UID: ");
for (byte i = 0; i < mfrc522.uid.size; i++) { if (mfrc522.uid.uidByte[i] < 0x10) { UID = UID + "0"; } UID = UID + String(mfrc522.uid.uidByte[i], HEX); if (i != mfrc522.uid.size - 1) { UID = UID + " "; } } UID.toUpperCase(); Serial.println(UID); mfrc522.PICC_HaltA(); return UID; }
`
Im thankful for every help i can get :)
— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/ChuckBell/MySQL_Connector_Arduino/issues/86, or mute the thread https://github.com/notifications/unsubscribe-auth/AH0j4MO7ZjxNIanP69gxqR62CY9039tiks5vRGDigaJpZM4bQ6Kp.
xIceFox
aguslopezz
KarcinMarkowski
Hello, I do a project where I read RFID Card System to check how long people are on a event. My Arduino is the MySQL Client, which reads the RFID Cards and call procedures on the SQL Server. Im using the MySQL Connector to run stored Procedures in MySQL. At the End of the Procedure in MySQL I do:
Select "Successful" or when the Procedure crashes: Select "Error"
Now I want to read this with Basic Select.
The Problem is: The First time I do the Basic Select, it works fine. I get the Information of the Procedure instantly.
The Second Time I do the Basic Select, I get an empty Line back.
The Third Time I do the Basic Select, I get an Bad mojo. EOF found reading column header. ERROR: You must read the columns first!.
I can post my Serial Monitor here:
I don't know why, but when I reset the Arduino, or I reconnect to the Server with the SoftReset, the first time it will work. The Problem is, that I haven't the time to soft reset my Arduino every time, because there are many people trying to get into this event.
My code is here:
Im thankful for every help i can get :)