Moved database connectionin loops of region for FACT_air

src/FACT_air.jl

@@ -19,7 +19,7 @@ This function queries a database for air traffic information, such as the number
 
 This example queries air traffic data for specified European regions and returns the results in a DataFrame.
 """
-function eu_air(conn::MySQL.Connection, selection::Dict)
+function eu_air(conn_dict::Dict, selection::Dict)
     # getting valuable info from dictionary: acceptable years are 1961, 71, 81, 91, 2001, 2011
     geo_id = selection["geo_id"]
     shape_obj = selection["shape_obj"]
@@ -29,8 +29,12 @@ function eu_air(conn::MySQL.Connection, selection::Dict)
     for (id, shape) in zip(geo_id, shape_obj)
         # prepare query
         query = "SELECT COUNT(DISTINCT(ea.airp_icao_)) as airports, SUM(et.flights) as flights FROM eu_airports_2013 ea JOIN eu_traffic et ON ea.airp_icao_ = et.ICAO_id WHERE ST_Intersects(ST_GeomFromText('"*shape*"'), ea.SHAPE) AND et.Year = 2022;"
+        # create connection
+        conn = establish_connection(conn_dict["host"], conn_dict["user"], conn_dict["password"], conn_dict["database"]; port=conn_dict["port"])
         # execute
         result = query_connection(conn, query)
+        # close connection
+        close_connection(conn)
         # Check if the result is empty
         if !isempty(result)
             # add geo_id col
@@ -67,7 +71,7 @@ This function queries a database for air traffic information, such as the number
 
 This example queries air traffic data for specified U.S. regions and returns the results in a DataFrame.
 """
-function us_air(conn::MySQL.Connection, selection::Dict)
+function us_air(conn_dict::Dict, selection::Dict)
     
     # getting valuable info from dictionary: acceptable years are 1961, 71, 81, 91, 2001, 2011
     geo_id = selection["geo_id"]
@@ -78,9 +82,12 @@ function us_air(conn::MySQL.Connection, selection::Dict)
     for (id, shape) in zip(geo_id, shape_obj)
         # prepare query
         query = "SELECT count(*) as airports, SUM(COALESCE(COMMERCIAL, 0) + COALESCE(COMMUTER_O, 0) + COALESCE(AIR_TAXI_O, 0) + COALESCE(LOCAL_OPS, 0) + COALESCE(ITNRNT_OPS, 0) + COALESCE(MIL_ACFT_O, 0)) as flights FROM us_airports WHERE ST_Intersects(ST_GeomFromText('"*shape*"'), SHAPE);"
-        
+        # create connection
+        conn = establish_connection(conn_dict["host"], conn_dict["user"], conn_dict["password"], conn_dict["database"]; port=conn_dict["port"])
         # execute
         result = query_connection(conn, query)
+        # close connection
+        close_connection(conn)
         # Check if the result is empty
         if !isempty(result)
             # add geo_id col
@@ -118,6 +125,14 @@ This function determines whether to fetch European or U.S. air traffic data base
 In this example, European air traffic data for the specified region is retrieved and returned in a DataFrame.
 """
 function get_airports_traffic(table::String, selection::Dict; host::String="127.0.0.1")
+    conn_dict = Dict(
+        "host" => host,
+        "port" => 3310,
+        "database" => "FACT_air",
+        "user" => "root",
+        "password" => "devops"
+    )
+
     table_dict = Dict(
         "eu_air" => eu_air,
         "us_air" => us_air
@@ -136,7 +151,7 @@ function get_airports_traffic(table::String, selection::Dict; host::String="127.
     end
 
     # data retrieval
-    df = get_selected_objects_from_table(table, df_template, table_dict, "FACT_air", selection; host=host, port=3310) 
+    df = get_selected_objects_from_table(table, df_template, table_dict, selection, conn_dict) 
     
     return df
 end

src/utils_DB_query.jl

@@ -158,7 +158,7 @@ selection = Dict("id" => 123)
 result = handle_selection_action("users", table_dict, conn, selection)
 ```
 """
-function handle_selection_action(table::String, table_dict::Dict, conn::MySQL.Connection, selection::Dict)
+function handle_selection_action(table::String, table_dict::Dict, conn_dict::Dict, selection::Dict)
     # Default function returns an empty DataFrame with an appropriate message
     default_func = () -> DataFrame(Message=["No corresponding table: $table"])
 
@@ -166,7 +166,7 @@ function handle_selection_action(table::String, table_dict::Dict, conn::MySQL.Co
     func = get(table_dict, table, default_func)
 
     # Call the function with the additional parameters
-    return func(conn, selection)
+    return func(conn_dict, selection)
 end
 
 """
@@ -198,12 +198,10 @@ database = "my_database"
 result_df = get_selected_objects_from_table("users", df, table_dict, database, selection)
 ```
 """
-function get_selected_objects_from_table(table::String, df::DataFrame, table_dict::Dict, database::String, selection::Dict; host::String="127.0.0.1", port::Int=3306)
+function get_selected_objects_from_table(table::String, df::DataFrame, table_dict::Dict, selection::Dict, conn_dict::Dict)
     
-    # Establish the connection
-    conn = establish_connection(host, "root", "devops", database; port=port)
     # get results
-    result = handle_selection_action(String(table), table_dict, conn, selection)
+    result = handle_selection_action(String(table), table_dict, conn_dict, selection)
     # start converting data types to fix mistakes in SQL types interpretation
     result = result[:, names(df)]
     # Check and convert each column in result to match the type in df
@@ -224,8 +222,5 @@ function get_selected_objects_from_table(table::String, df::DataFrame, table_dic
     end
     df = vcat(df, result)
 
-    # Close the connection when done
-    close_connection(conn)
-
     return df
 end