working example with write and select

Cargo.lock

@@ -460,6 +460,7 @@ dependencies = [
  "num-integer",
  "num-traits",
  "pq-sys",
+ "r2d2",
  "serde_json",
 ]
 
@@ -1088,6 +1089,17 @@ version = "5.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "69cdb34c158ceb288df11e18b4bd39de994f6657d83847bdffdbd7f346754b0f"
 
+[[package]]
+name = "r2d2"
+version = "0.8.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "51de85fb3fb6524929c8a2eb85e6b6d363de4e8c48f9e2c2eac4944abc181c93"
+dependencies = [
+ "log",
+ "parking_lot",
+ "scheduled-thread-pool",
+]
+
 [[package]]
 name = "rand"
 version = "0.9.2"
@@ -1176,6 +1188,15 @@ version = "1.0.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a50f4cf475b65d88e057964e0e9bb1f0aa9bbb2036dc65c64596b42932536984"
 
+[[package]]
+name = "scheduled-thread-pool"
+version = "0.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3cbc66816425a074528352f5789333ecff06ca41b36b0b0efdfbb29edc391a19"
+dependencies = [
+ "parking_lot",
+]
+
 [[package]]
 name = "schema"
 version = "0.1.0"