diff --git a/DESCRIPTION b/DESCRIPTION
index 609f6ed..6c89f9b 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: tarflow.iquizoo
 Title: Setup "targets" Workflows for "iquizoo" Data Processing
-Version: 3.12.2
+Version: 3.12.3
 Authors@R: c(
     person("Liang", "Zhang", , "psychelzh@outlook.com", role = c("aut", "cre"),
            comment = c(ORCID = "0000-0001-9041-1150")),
@@ -25,6 +25,7 @@ Imports:
     jsonlite,
     memoise,
     rlang (>= 1.0.0),
+    RMariaDB,
     tarchetypes,
     targets
 Suggests:
@@ -33,9 +34,7 @@ Suggests:
     data.iquizoo (>= 2024.7.14),
     digest,
     lifecycle,
-    odbc,
     preproc.iquizoo (>= 2.6.0),
-    RMariaDB (>= 1.3.1),
     roxygen2,
     testthat (>= 3.0.0),
     tibble
diff --git a/NAMESPACE b/NAMESPACE
index 82e825b..ac5cbe4 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -7,7 +7,6 @@ export(fetch_iquizoo_mem)
 export(get_users_props_names)
 export(parse_data)
 export(setup_option_file)
-export(setup_source)
 export(setup_templates)
 export(tar_fetch_data)
 export(tar_fetch_users)
diff --git a/NEWS.md b/NEWS.md
index b51eeda..24a2c24 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,3 +1,10 @@
+# tarflow.iquizoo 3.12.3
+
+## Upkeep
+
+* Dropped support for odbc driver, and only RMariaDB driver is supported now (#93).
+* Removed `setup_source()` for there is no need for database source option setup when only `RMariaDB::MariaDB()` is supported.
+
 # tarflow.iquizoo 3.12.2
 
 ## Enhancements
diff --git a/R/database.R b/R/database.R
index 4ddb718..9c7e2dd 100644
--- a/R/database.R
+++ b/R/database.R
@@ -4,36 +4,16 @@
 #' @param ... Further arguments passed to [DBI::dbConnect()].
 #' @param params The parameters to be bound to the query. Default to `NULL`, see
 #'   [DBI::dbGetQuery()] for more details.
-#' @param source The data source from which data is fetched. See
-#'   [setup_source()] for details.
+#' @param group Section identifier in the `default.file`. See
+#'   [RMariaDB::MariaDB()] for more information.
 #' @return A [data.frame] contains the fetched data.
 #' @seealso [fetch_iquizoo_mem()] for a memoised version of this function.
 #' @export
 fetch_iquizoo <- function(query, ...,
                           params = NULL,
-                          source = setup_source()) {
+                          group = getOption("tarflow.group")) {
   check_dots_used()
-  if (!inherits(source, "tarflow.source")) {
-    cli::cli_abort(
-      "{.arg source} must be created by {.fun setup_source}.",
-      class = "tarflow_bad_source"
-    )
-  }
-  # connect to given database which is pre-configured
-  if (!inherits_any(source$driver, c("OdbcDriver", "MariaDBDriver"))) {
-    cli::cli_abort(
-      "Driver must be either OdbcDriver or MariaDBDriver.",
-      class = "tarflow_bad_driver"
-    )
-  }
-  # nocov start
-  if (inherits(source$driver, "OdbcDriver")) {
-    con <- DBI::dbConnect(source$driver, dsn = source$dsn, ...)
-  }
-  # nocov end
-  if (inherits(source$driver, "MariaDBDriver")) {
-    con <- DBI::dbConnect(source$driver, group = source$group, ...)
-  }
+  con <- DBI::dbConnect(RMariaDB::MariaDB(), group = group, ...)
   on.exit(DBI::dbDisconnect(con))
   DBI::dbGetQuery(con, query, params = params)
 }
diff --git a/R/setup.R b/R/setup.R
index 4f1ddf5..439cc6c 100644
--- a/R/setup.R
+++ b/R/setup.R
@@ -37,54 +37,14 @@ setup_templates <- function(contents = NULL,
   )
 }
 
-#' Set data source
-#'
-#' @param driver The driver used. Set as an option of `"tarflow.driver"`.
-#'   Options are [odbc::odbc()] and [RMariaDB::MariaDB()], both of which need
-#'   pre-configurations. Default to first available one.
-#' @param dsn The data source name of an **ODBC** database connector. See
-#'   [odbc::dbConnect()] for more information. Used when `driver` is set as
-#'   [odbc::odbc()].
-#' @param group Section identifier in the `default.file`. See
-#'   [RMariaDB::MariaDB()] for more information. Used when `driver` is set as
-#'   [RMariaDB::MariaDB()].
-#' @return An S3 class of `tarflow.source` with the options.
-#' @export
-setup_source <- function(driver = getOption("tarflow.driver"),
-                         dsn = getOption("tarflow.dsn"),
-                         group = getOption("tarflow.group")) {
-  structure(
-    list(
-      driver = driver,
-      dsn = dsn,
-      group = group
-    ),
-    class = "tarflow.source"
-  )
-}
-
 #' Check if the database based on the given data source is ready
 #'
-#' @param source The data source from which data is fetched. See
-#'    [setup_source()] for details.
+#' @param group Section identifier in the `default.file`. See
+#'   [RMariaDB::MariaDB()] for more information.
 #' @return TRUE if the database is ready, FALSE otherwise.
 #' @export
-check_source <- function(source = setup_source()) {
-  if (!inherits(source, "tarflow.source")) {
-    cli::cli_abort(
-      "{.arg source} must be created by {.fun setup_source}.",
-      class = "tarflow_bad_source"
-    )
-  }
-  # nocov start
-  if (inherits(source$driver, "OdbcDriver")) {
-    return(DBI::dbCanConnect(source$driver, dsn = source$dsn))
-  }
-  # nocov end
-  if (inherits(source$driver, "MariaDBDriver")) {
-    return(DBI::dbCanConnect(source$driver, group = source$group))
-  }
-  return(FALSE)
+check_source <- function(group = getOption("tarflow.group")) {
+  return(DBI::dbCanConnect(RMariaDB::MariaDB(), group = group))
 }
 
 # nocov start
diff --git a/R/targets.R b/R/targets.R
index 41a9625..a51e917 100644
--- a/R/targets.R
+++ b/R/targets.R
@@ -185,7 +185,7 @@ tar_fetch_users <- function(contents, subset_users_props = NULL,
       bquote(
         fetch_iquizoo(
           .(glue::glue(read_file(templates[["users"]]),
-            .envir = list(columns = columns)
+            .envir = env(columns = columns)
           )),
           params = list(.(unique(contents$project_id)))
         ) |>
diff --git a/R/zzz.R b/R/zzz.R
index 0971106..cf57234 100644
--- a/R/zzz.R
+++ b/R/zzz.R
@@ -4,26 +4,13 @@ NULL
 # nocov start
 
 .onLoad <- function(libname, pkgname) {
-  # options
+  # setup options
   op <- options()
-  name_db_src_default <- "iquizoo-v3"
-  if (requireNamespace("RMariaDB", quietly = TRUE)) {
-    op_tarflow <- list(
-      tarflow.driver = RMariaDB::MariaDB(),
-      tarflow.group = name_db_src_default
-    )
-  } else if (requireNamespace("odbc", quietly = TRUE)) {
-    op_tarflow <- list(
-      tarflow.driver = odbc::odbc(),
-      tarflow.dsn = name_db_src_default
-    )
-  } else {
-    op_tarflow <- list()
-  }
-
+  op_tarflow <- list(tarflow.group = "iquizoo-v3")
   toset <- !(names(op_tarflow) %in% names(op))
   if (any(toset)) options(op_tarflow[toset])
 
+  # try setting up option file if source not working
   if (!check_source()) {
     tryCatch(setup_option_file(quietly = TRUE), error = \(e) {})
   }
@@ -32,14 +19,7 @@ NULL
 }
 
 .onAttach <- function(libname, pkgname) {
-  if (!requireNamespace("odbc", quietly = TRUE) &&
-        !requireNamespace("RMariaDB", quietly = TRUE)) {
-    packageStartupMessage(
-      "Neither odbc nor RMariaDB is installed.",
-      " For better support, it is recommended to install RMariaDB.",
-      " Please install it with `install.packages('RMariaDB')`."
-    )
-  } else if (!check_source()) {
+  if (!check_source()) {
     packageStartupMessage(
       "The default database source is not working.",
       " Please check your database settings first.",
diff --git a/_pkgdown.yml b/_pkgdown.yml
index 83e2440..1488f75 100644
--- a/_pkgdown.yml
+++ b/_pkgdown.yml
@@ -23,7 +23,6 @@ reference:
   desc: Functions to help you set up options.
   contents:
   - setup_templates
-  - setup_source
   - setup_option_file
   - check_source
   - get_users_props_names
diff --git a/man/check_source.Rd b/man/check_source.Rd
index 0114107..a3dbc23 100644
--- a/man/check_source.Rd
+++ b/man/check_source.Rd
@@ -4,11 +4,11 @@
 \alias{check_source}
 \title{Check if the database based on the given data source is ready}
 \usage{
-check_source(source = setup_source())
+check_source(group = getOption("tarflow.group"))
 }
 \arguments{
-\item{source}{The data source from which data is fetched. See
-\code{\link[=setup_source]{setup_source()}} for details.}
+\item{group}{Section identifier in the \code{default.file}. See
+\code{\link[RMariaDB:dbConnect-MariaDBDriver-method]{RMariaDB::MariaDB()}} for more information.}
 }
 \value{
 TRUE if the database is ready, FALSE otherwise.
diff --git a/man/fetch_iquizoo.Rd b/man/fetch_iquizoo.Rd
index 4104f1a..a73658a 100644
--- a/man/fetch_iquizoo.Rd
+++ b/man/fetch_iquizoo.Rd
@@ -4,7 +4,7 @@
 \alias{fetch_iquizoo}
 \title{Fetch result of query from iQuizoo database}
 \usage{
-fetch_iquizoo(query, ..., params = NULL, source = setup_source())
+fetch_iquizoo(query, ..., params = NULL, group = getOption("tarflow.group"))
 }
 \arguments{
 \item{query}{A character string containing SQL.}
@@ -14,8 +14,8 @@ fetch_iquizoo(query, ..., params = NULL, source = setup_source())
 \item{params}{The parameters to be bound to the query. Default to \code{NULL}, see
 \code{\link[DBI:dbGetQuery]{DBI::dbGetQuery()}} for more details.}
 
-\item{source}{The data source from which data is fetched. See
-\code{\link[=setup_source]{setup_source()}} for details.}
+\item{group}{Section identifier in the \code{default.file}. See
+\code{\link[RMariaDB:dbConnect-MariaDBDriver-method]{RMariaDB::MariaDB()}} for more information.}
 }
 \value{
 A \link{data.frame} contains the fetched data.
diff --git a/man/setup_source.Rd b/man/setup_source.Rd
deleted file mode 100644
index 5be8e03..0000000
--- a/man/setup_source.Rd
+++ /dev/null
@@ -1,31 +0,0 @@
-% Generated by roxygen2: do not edit by hand
-% Please edit documentation in R/setup.R
-\name{setup_source}
-\alias{setup_source}
-\title{Set data source}
-\usage{
-setup_source(
-  driver = getOption("tarflow.driver"),
-  dsn = getOption("tarflow.dsn"),
-  group = getOption("tarflow.group")
-)
-}
-\arguments{
-\item{driver}{The driver used. Set as an option of \code{"tarflow.driver"}.
-Options are \code{\link[odbc:dbConnect-OdbcDriver-method]{odbc::odbc()}} and \code{\link[RMariaDB:dbConnect-MariaDBDriver-method]{RMariaDB::MariaDB()}}, both of which need
-pre-configurations. Default to first available one.}
-
-\item{dsn}{The data source name of an \strong{ODBC} database connector. See
-\code{\link[odbc:dbConnect-OdbcDriver-method]{odbc::dbConnect()}} for more information. Used when \code{driver} is set as
-\code{\link[odbc:dbConnect-OdbcDriver-method]{odbc::odbc()}}.}
-
-\item{group}{Section identifier in the \code{default.file}. See
-\code{\link[RMariaDB:dbConnect-MariaDBDriver-method]{RMariaDB::MariaDB()}} for more information. Used when \code{driver} is set as
-\code{\link[RMariaDB:dbConnect-MariaDBDriver-method]{RMariaDB::MariaDB()}}.}
-}
-\value{
-An S3 class of \code{tarflow.source} with the options.
-}
-\description{
-Set data source
-}
diff --git a/tests/testthat/test-database.R b/tests/testthat/test-database.R
index ab73c59..f229262 100644
--- a/tests/testthat/test-database.R
+++ b/tests/testthat/test-database.R
@@ -1,16 +1,3 @@
-test_that("Ensure source checking works", {
-  source <- list(driver = RMariaDB::MariaDB())
-  fetch_iquizoo(source = source) |>
-    expect_error(class = "tarflow_bad_source")
-  check_source(source = source) |>
-    expect_error(class = "tarflow_bad_source")
-  source_invalid <- setup_source(driver = NULL)
-  fetch_iquizoo(source = source_invalid) |>
-    expect_error(class = "tarflow_bad_driver")
-  check_source(source = source_invalid) |>
-    expect_false()
-})
-
 test_that("`parse_data()` works", {
   js_str <- r"([{"a": 1, "b": 2}])"
   data <- data.frame(game_data = js_str)