can corona be able to open an MySQL DB? - database

Question

just wondering, if MySQL can be used in corona or MySQL db's can be opened using sqlite3
or is there any difference If I use a MySQL db or sqlite3 db?

Answer 1

Corona provides its own library for connection to SQLite drivers, whose document can be accessed here.
local sqlite3 = require "sqlite3"
--Open data.db. If the file doesn't exist it will be created
local path = system.pathForFile("data.db", system.DocumentsDirectory)
db = sqlite3.open( path )
--Handle the applicationExit event to close the db
local function onSystemEvent( event )
if( event.type == "applicationExit" ) then
db:close()
end
end
--Setup the table if it doesn't exist
local tablesetup = [[CREATE TABLE IF NOT EXISTS test (id INTEGER PRIMARY KEY, content, content2);]]
print(tablesetup)
db:exec( tablesetup )
--Add rows with a auto index in 'id'. You don't need to specify a set of values because we're populating all of them
local testvalue = {}
testvalue[1] = 'Hello'
testvalue[2] = 'World'
testvalue[3] = 'Lua'
local tablefill =[[INSERT INTO test VALUES (NULL, ']]..testvalue[1]..[[',']]..testvalue[2]..[['); ]]
local tablefill2 =[[INSERT INTO test VALUES (NULL, ']]..testvalue[2]..[[',']]..testvalue[1]..[['); ]]
local tablefill3 =[[INSERT INTO test VALUES (NULL, ']]..testvalue[1]..[[',']]..testvalue[3]..[['); ]]
db:exec( tablefill )
db:exec( tablefill2 )
db:exec( tablefill3 )
--print the sqlite version to the terminal
print( "version " .. sqlite3.version() )
--print all the table contents
for row in db:nrows("SELECT * FROM test") do
local text = row.content.." "..row.content2
local t = display.newText(text, 20, 30 * row.id, null, 16)
t:setFillColor( 1, 0, 1 )
end
--setup the system listener to catch applicationExit
Runtime:addEventListener( "system", onSystemEvent )
You can also use third party libraries (or batteries) for creating connections. One such library common in use is LuaSQL.
A thread on the Corona community shows you how to establish connection using LuaSQL for MySQL servers.
local luasql = require "luasql.mysql";
env = assert((luasql.mysql()), "Uh oh, couldn't load driver")
conn = assert(env:connect("database","username","password","localhost"), "Oops!!")
cur = assert (conn:execute ("SELECT * from table_1" ))
row = cur:fetch ({}, "a")
while row do
print ("\n------ new row ---------\n")
table.foreach (row, print)
row = cur:fetch (row, "a")
end
cur:close()
conn:close()
env:close()