add get cities handler and improve db schema

service_a/internal/domains/meteo/repository.go

@@ -11,6 +11,7 @@ import (
 type Repository interface {
 	InsertMeteoDataTX(ctx context.Context, params InsertMeteoDataParams) (*InsertMeteoDataResult, error)
 	UpdateBatchElapsedTime(ctx context.Context, batchID int, elapsedMS int) error
+	GetCities(ctx context.Context) []string
 	GetMeteoData(ctx context.Context, params GetMeteoData) ([]MeteoData, error)
 }
 
@@ -150,10 +151,32 @@ func (pgx *pgxRepo) UpdateBatchElapsedTime(ctx context.Context, batchID int, ela
 	return nil
 }
 
-const getMeteoDataQuery = `
+const getCities = `select distinct location_name from public.meteo_data order by location_name`
+
+func (pgx *pgxRepo) GetCities(ctx context.Context) []string {
+	rows, err := pgx.Query(ctx, getCities)
+	if err != nil {
+		return []string{}
+	}
+	defer rows.Close()
+
+	var cities []string
+	for rows.Next() {
+		var city string
+		err := rows.Scan(&city)
+		if err != nil {
+			continue
+		}
+		cities = append(cities, city)
+	}
+
+	return cities
+}
+
+const getMeteoData = `
 	select location_name, date_of_register, max_temp, min_temp, rainfall, cloudiness
 	from public.meteo_data
-	where location_name = $1
+	where location_name_norm = unaccent(lower($1))
 		and date_of_register >= $2
 		and date_of_register <= $3
 	order by date_of_register desc
@@ -161,7 +184,7 @@ const getMeteoDataQuery = `
 `
 
 func (pgx *pgxRepo) GetMeteoData(ctx context.Context, params GetMeteoData) ([]MeteoData, error) {
-	rows, err := pgx.Query(ctx, getMeteoDataQuery, params.Location, params.From, params.To, params.Limit, params.Offset)
+	rows, err := pgx.Query(ctx, getMeteoData, params.Location, params.From, params.To, params.Limit, params.Offset)
 	if err != nil {
 		return nil, fmt.Errorf("error querying meteo data: %w", err)
 	}