[HELP] Database cannot connect !

[Mσнαмα∂ Hєℓιѕн]

hi guys.

 

this is my mysql connection script :

function connectToDatabase(res)
	MySQLConnection = mysqlconnect(hostname, username, password, database, port)
	
	if (not MySQLConnection) then
		if (res == getThisResource()) then
			cancelEvent(true, "Cannot connect to the database.")
		end
		return nil
	end
	
	return nil
end
addEventHandler("onResourceStart", getResourceRootElement(getThisResource()), connectToDatabase, false)

 

and errors is :

attempt to call global 'mysqlconnect' (a nil value)

 

plz debug my database connection script

 

[WorthlessCynomys]

This says that the function mysqlconnect is a not existing function. That is true. Do you use some kind of .dll or .so file to handle mysql?

[Mσнαмα∂ Hєℓιѕн]

Just now, WorthlessCynomys said:

This says that the function mysqlconnect is a not existing function. That is true. Do you use some kind of .dll or .so file to handle mysql?

no!

my mysql file is arnika.sql

[WorthlessCynomys]

Just now, Mσнαмα∂ Hєℓιѕн said:

no!

my mysql file is arnika.sql

.sql files are containing the databases and tables. You have to use MTA's internal database functions

dbConnect()
dbQuery()
dbPoll()
dbExec()

To handle MySQL. You can connect to your database with dbConnect. There's no such function as mysqlconnect.

[Mσнαмα∂ Hєℓιѕн]

Just now, WorthlessCynomys said:

.sql files are containing the databases and tables. You have to use MTA's internal database functions

dbConnect()
dbQuery()
dbPoll()
dbExec()

To handle MySQL. You can connect to your database with dbConnect. There's no such function as mysqlconnect.

how ?

i don't know work with internal database functions

 

you can help me?

[WorthlessCynomys]

Go to the WIKI page of dbConnect. There are example lines that can be copy pasted into your code, so like if you use MySQL, then you copy paste the MySQL line, fill it out with your data and it will connect.

 

This is how you do the connection part. Doing anything other than this is done by the other 3 functions. Selecting data from the database is done with dbQuery. You have to provide the MySQL connection to it, then write an SQL query to select the data you want. An SQL query looks somehow like this: "SELECT * FROM accounts WHERE id=?". This will select everything in accounts table where the value of id equals to what you gave to it as an argument.

It looks like this:

queryhandle = dbQuery(connection, "SELECT * FROM accounts WHERE id=?", id);

The value of id in the query will be the value of the variable id.

You can process the retrieved data with dbPoll:

result = dbPoll(queryhandle, 500);

This will give you a Lua table containing the lines that you got back. You can work with that table using a for cycle:

for i, row in ipairs(result) do -- i stands for Index and row stands for the rows that you got back from the database.
  outputChatBox(row["username"]); -- This will output the username value of every line.
end

If you don't want any return values at an update or insert, you can use dbExec:

dbExec(connection, "INSERT INTO accounts SET username=?", username);

These are the very basics. MySQL isn't hard, it's just a complete mess and this makes it hard to understand. Once you feel it, it's one of the easiest things in the world :D.

Good luck.

[Mσнαмα∂ Hєℓιѕн]

8 minutes ago, WorthlessCynomys said:

Go to the WIKI page of dbConnect. There are example lines that can be copy pasted into your code, so like if you use MySQL, then you copy paste the MySQL line, fill it out with your data and it will connect.

 

This is how you do the connection part. Doing anything other than this is done by the other 3 functions. Selecting data from the database is done with dbQuery. You have to provide the MySQL connection to it, then write an SQL query to select the data you want. An SQL query looks somehow like this: "SELECT * FROM accounts WHERE id=?". This will select everything in accounts table where the value of id equals to what you gave to it as an argument.

It looks like this:

queryhandle = dbQuery(connection, "SELECT * FROM accounts WHERE id=?", id);

The value of id in the query will be the value of the variable id.

You can process the retrieved data with dbPoll:

result = dbPoll(queryhandle, 500);

This will give you a Lua table containing the lines that you got back. You can work with that table using a for cycle:

for i, row in ipairs(result) do -- i stands for Index and row stands for the rows that you got back from the database.
  outputChatBox(row["username"]); -- This will output the username value of every line.
end

If you don't want any return values at an update or insert, you can use dbExec:

dbExec(connection, "INSERT INTO accounts SET username=?", username);

These are the very basics. MySQL isn't hard, it's just a complete mess and this makes it hard to understand. Once you feel it, it's one of the easiest things in the world :D.

Good luck.

i understand

Good LuCk!