diff --git a/.tool-versions b/.tool-versions
new file mode 100644
index 00000000..e94aeff9
--- /dev/null
+++ b/.tool-versions
@@ -0,0 +1 @@
+lua 5.3.6
diff --git a/lua/sqlite/parser.lua b/lua/sqlite/parser.lua
index 1c677e15..b20d08ff 100644
--- a/lua/sqlite/parser.lua
+++ b/lua/sqlite/parser.lua
@@ -125,8 +125,8 @@ local pvalues = function(defs, kv)
 
   local keys = {}
   for k, v in u.opairs(defs) do
-    if type(v) == "string" and v:match "^[%S]+%(.*%)$" then
-      tinsert(keys, v)
+    if type(v) == "function" then
+      tinsert(keys, v())
     else
       tinsert(keys, ":" .. k)
     end
@@ -270,7 +270,8 @@ local pselect = function(select)
       if type(k) == "number" then
         tinsert(items, v)
       else
-        tinsert(items, ("%s as %s"):format(v, k))
+        local z = type(v) == "function" and v() or v
+        tinsert(items, ("%s as %s"):format(z, k))
       end
     end
 
@@ -346,7 +347,7 @@ local opts_to_str = function(tbl)
       end
     end,
     default = function(v)
-      v = (type(v) == "string" and v:match "^[%S]+%(.*%)$") and "(" .. tostring(v) .. ")" or v
+      v = type(v) == "function" and "(" .. tostring(v()) .. ")" or v
       local str = "default "
       if tbl["required"] then
         return "on conflict replace " .. str .. v
diff --git a/lua/sqlite/stmt.lua b/lua/sqlite/stmt.lua
index a2d3d3d1..32383b13 100644
--- a/lua/sqlite/stmt.lua
+++ b/lua/sqlite/stmt.lua
@@ -302,7 +302,7 @@ function sqlstmt:bind(...)
 
     for k, v in pairs(names) do
       local index = parameter_index_cache[k] or table.remove(anon_indices, 1)
-      if ((type(v) == "string" and v:match "^[%S]+%(.*%)$") and flags.ok or self:bind(index, v)) ~= flags.ok then
+      if ((type(v) == "function") and flags.ok or self:bind(index, v)) ~= flags.ok then
         error("sqlite.lua error at stmt:bind(), failed to bind a given value '%s'. Please report issue."):format(v)
       end
     end
diff --git a/lua/sqlite/strfun.lua b/lua/sqlite/strfun.lua
index 420c9e18..38b25344 100644
--- a/lua/sqlite/strfun.lua
+++ b/lua/sqlite/strfun.lua
@@ -67,7 +67,7 @@ end
 ---@usage `sqlstrftime('%s','now') - strftime('%s','2014-10-07 02:34:56')` -> 2110042
 M.strftime = function(format, timestring)
   local str = [[strftime('%s', %s)]]
-  return customstr(str:format(format, ts(timestring)))
+  return M.fn(str:format(format, ts(timestring)))
 end
 
 ---Return the number of days since noon in Greenwich on November 24, 4714 B.C.
@@ -132,4 +132,10 @@ M.cast = function(source, as)
   return string.format("cast(%s as %s)", source, as)
 end
 
+M.fn = function(s)
+  return function()
+    return s
+  end
+end
+
 return M
diff --git a/test/auto/db_spec.lua b/test/auto/db_spec.lua
index f7412b65..d1ba12a4 100644
--- a/test/auto/db_spec.lua
+++ b/test/auto/db_spec.lua
@@ -384,7 +384,10 @@ describe("sqlite.db", function()
 
     it("evaluates sqlite functions", function()
       db:eval "create table testa(id integer primary key, date text, title text)"
-      db:insert("testa", { title = "fd", date = db.lib.strftime "%H:%M:%S" })
+      db:insert("testa", {
+        title = "fd",
+        date = db.lib.strftime "%H:%M:%S",
+      })
 
       local res = db:eval [[select * from testa]]
       eq(os.date "!%H:%M:%S", res[1].date)
@@ -546,9 +549,9 @@ describe("sqlite.db", function()
   end)
 
   describe(":select", function()
-    if vim.fn.executable("curl") then
-        pending("'curl' program is not available")
-        return
+    if vim.fn.executable "curl" then
+      pending "'curl' program is not available"
+      return
     end
     local db = sql:open(path)
     local posts, users
diff --git a/test/auto/parser_spec.lua b/test/auto/parser_spec.lua
index 4ffc56f9..d7185b91 100644
--- a/test/auto/parser_spec.lua
+++ b/test/auto/parser_spec.lua
@@ -1,4 +1,5 @@
 local p = require "sqlite.parser"
+local fn = require("sqlite.strfun").fn
 local eq = assert.are.same
 
 describe("parse", function()
@@ -8,7 +9,7 @@ describe("parse", function()
       eq(
         "insert into todo (date, id) values(date('now'), :id)",
         p.insert(tbl, { values = {
-          date = "date('now')",
+          date = fn "date('now')",
           id = 1,
         } })
       )
@@ -257,6 +258,20 @@ describe("parse", function()
     end)
   end)
 
+  describe("[select]", function()
+    it('works with [select] = "a single string"', function()
+      local defs = {
+        select = {
+          "id",
+          z = fn "date('now')",
+        },
+      }
+      local expected = "select id, date('now') as z from people"
+      local passed = p.select("people", defs)
+      eq(expected, passed, "should be identical")
+    end)
+  end)
+
   describe("[order by]", function()
     it("works with signle table name", function()
       local defs = {