users 정보 페이지 구현

backend/internal/repository/clickhouse_repo.go

@@ -15,6 +15,21 @@ type ClickHouseRepository struct {
 }
 
 func NewClickHouseRepository(host string, port int, user, password, db string) (*ClickHouseRepository, error) {
+	// 1. Connect to 'default' database first to ensure target DB exists
+	tmpConn, err := clickhouse.Open(&clickhouse.Options{
+		Addr: []string{fmt.Sprintf("%s:%d", host, port)},
+		Auth: clickhouse.Auth{
+			Database: "default",
+			Username: user,
+			Password: password,
+		},
+	})
+	if err == nil {
+		_ = tmpConn.Exec(context.Background(), fmt.Sprintf("CREATE DATABASE IF NOT EXISTS %s", db))
+		_ = tmpConn.Close()
+	}
+
+	// 2. Now connect to the target database
 	conn, err := clickhouse.Open(&clickhouse.Options{
 		Addr: []string{fmt.Sprintf("%s:%d", host, port)},
 		Auth: clickhouse.Auth{