Merge pull request #2 from planetscale/fix-FOREIGN_KEY_CHECKS

set `foreign_key_checks` to `1` if `use_fk=1`

tpcc_common.lua

@@ -97,8 +97,10 @@ function db_connection_init()
 
    set_isolation_level(drv,con)
 
-   if drv:name() == "mysql" then 
-      con:query("SET FOREIGN_KEY_CHECKS=0")
+   if drv:name() == "mysql" then
+      if sysbench.opt.use_fk == 0 then
+        con:query("SET FOREIGN_KEY_CHECKS=0")
+      end
       con:query("SET autocommit=0")
    end
 
@@ -642,6 +644,9 @@ function cleanup()
 
    local drv,con = db_connection_init()
 
+   if sysbench.opt.use_fk == 1 then
+      con:query("SET FOREIGN_KEY_CHECKS=0")
+   end
    for i = 1, sysbench.opt.tables do
       print(string.format("Dropping tables '%d'...", i))
       con:query("DROP TABLE IF EXISTS history" .. i )
@@ -654,6 +659,9 @@ function cleanup()
       con:query("DROP TABLE IF EXISTS item" .. i )
       con:query("DROP TABLE IF EXISTS warehouse" .. i )
    end
+   if sysbench.opt.use_fk == 1 then
+      con:query("SET FOREIGN_KEY_CHECKS=1")
+   end
 end
 
 function Lastname(num)