From 74e5713750a07b5557c64b04303d990f58cd0a31 Mon Sep 17 00:00:00 2001
From: tstephen-nhs <231503406+tstephen-nhs@users.noreply.github.com>
Date: Wed, 25 Mar 2026 14:36:05 +0000
Subject: [PATCH 1/2] fix: new index for post dated

---
 SAMtemplates/tables/main.yaml                 | 23 +++++++++++++++++--
 packages/gsul/src/dynamoDBclient.ts           |  3 ++-
 .../gsul/tests/testRunDynamoDBQueries.test.ts |  2 +-
 3 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/SAMtemplates/tables/main.yaml b/SAMtemplates/tables/main.yaml
index b0c232c21c..e0185c2df4 100644
--- a/SAMtemplates/tables/main.yaml
+++ b/SAMtemplates/tables/main.yaml
@@ -184,8 +184,6 @@ Resources:
               - TerminalStatus
               - LastModified
               - Status
-                # TODO: Remove this when we deprecate post dated prescriptions.
-              - PostDatedLastModifiedSetAt
             ProjectionType: INCLUDE
           ProvisionedThroughput: !If
             - EnableDynamoDBAutoScalingCondition
@@ -222,6 +220,27 @@ Resources:
             - ReadCapacityUnits: 1
               WriteCapacityUnits: !Ref MinWritePrescriptionStatusUpdatesCapacity
             - !Ref "AWS::NoValue"
+        - IndexName: PharmacyODSCodePrescriptionIDIndexIncPostDated
+          KeySchema:
+            - AttributeName: PharmacyODSCode
+              KeyType: HASH
+            - AttributeName: PrescriptionID
+              KeyType: RANGE
+          Projection:
+            NonKeyAttributes:
+              - PatientNHSNumber
+              - LineItemID
+              - TerminalStatus
+              - LastModified
+              - Status
+                # TODO: Remove this when we deprecate post dated prescriptions.
+              - PostDatedLastModifiedSetAt
+            ProjectionType: INCLUDE
+          ProvisionedThroughput: !If
+            - EnableDynamoDBAutoScalingCondition
+            - ReadCapacityUnits: 1
+              WriteCapacityUnits: !Ref MinWritePrescriptionStatusUpdatesCapacity
+            - !Ref "AWS::NoValue"            
       Tags:
         - Key: "EPS-Tablename"
           Value: "PrescriptionStatusUpdates"
diff --git a/packages/gsul/src/dynamoDBclient.ts b/packages/gsul/src/dynamoDBclient.ts
index 1aa871bd39..39ab3eb62d 100644
--- a/packages/gsul/src/dynamoDBclient.ts
+++ b/packages/gsul/src/dynamoDBclient.ts
@@ -50,7 +50,8 @@ export async function getItemsUpdatesForPrescription(
 export function createQueryCommandInput(odsCode: string, prescriptionID: string): QueryCommandInput {
   return {
     TableName: tableName,
-    IndexName: "PharmacyODSCodePrescriptionIDIndex",
+    // TODO: revert to PharmacyODSCodePrescriptionIDIndex once post-dated no longer required
+    IndexName: "PharmacyODSCodePrescriptionIDIndexIncPostDated",
     KeyConditionExpression: "PrescriptionID = :inputPrescriptionID AND PharmacyODSCode = :inputPharmacyODSCode",
     ExpressionAttributeValues: {
       ":inputPharmacyODSCode": odsCode.toUpperCase(),
diff --git a/packages/gsul/tests/testRunDynamoDBQueries.test.ts b/packages/gsul/tests/testRunDynamoDBQueries.test.ts
index 2371588b07..b60c00e1b2 100644
--- a/packages/gsul/tests/testRunDynamoDBQueries.test.ts
+++ b/packages/gsul/tests/testRunDynamoDBQueries.test.ts
@@ -48,7 +48,7 @@ describe("testing dynamoDBClient", () => {
 
     const expected = {
       TableName: undefined,
-      IndexName: "PharmacyODSCodePrescriptionIDIndex",
+      IndexName: "PharmacyODSCodePrescriptionIDIndexIncPostDated",
       KeyConditionExpression: "PrescriptionID = :inputPrescriptionID AND PharmacyODSCode = :inputPharmacyODSCode",
       ExpressionAttributeValues: {
         ":inputPharmacyODSCode": "ODSCODE",

From 7a6d1e8956aaaa6d16b13a372a65f582fa3ee340 Mon Sep 17 00:00:00 2001
From: tstephen-nhs <231503406+tstephen-nhs@users.noreply.github.com>
Date: Wed, 25 Mar 2026 15:16:02 +0000
Subject: [PATCH 2/2] chore: add scaling policy for new index

---
 SAMtemplates/tables/main.yaml | 54 +++++++++++++++++++++++++++++++++--
 1 file changed, 52 insertions(+), 2 deletions(-)

diff --git a/SAMtemplates/tables/main.yaml b/SAMtemplates/tables/main.yaml
index e0185c2df4..666479584f 100644
--- a/SAMtemplates/tables/main.yaml
+++ b/SAMtemplates/tables/main.yaml
@@ -233,14 +233,14 @@ Resources:
               - TerminalStatus
               - LastModified
               - Status
-                # TODO: Remove this when we deprecate post dated prescriptions.
+              # TODO: Remove this when we deprecate post dated prescriptions.
               - PostDatedLastModifiedSetAt
             ProjectionType: INCLUDE
           ProvisionedThroughput: !If
             - EnableDynamoDBAutoScalingCondition
             - ReadCapacityUnits: 1
               WriteCapacityUnits: !Ref MinWritePrescriptionStatusUpdatesCapacity
-            - !Ref "AWS::NoValue"            
+            - !Ref "AWS::NoValue"
       Tags:
         - Key: "EPS-Tablename"
           Value: "PrescriptionStatusUpdates"
@@ -356,6 +356,56 @@ Resources:
         PredefinedMetricSpecification:
           PredefinedMetricType: DynamoDBReadCapacityUtilization
 
+  PharmacyIndexIncPostDatedScalingWriteTarget:
+    Type: AWS::ApplicationAutoScaling::ScalableTarget
+    Condition: EnableDynamoDBAutoScalingCondition
+    Properties:
+      MinCapacity: !Ref MinWritePrescriptionStatusUpdatesCapacity
+      MaxCapacity: !Ref MaxWritePrescriptionStatusUpdatesCapacity
+      ResourceId: !Sub table/${PrescriptionStatusUpdatesTable}/index/PharmacyODSCodePrescriptionIDIndexIncPostDated
+      RoleARN: !GetAtt DynamoDbScalingRole.Arn
+      ScalableDimension: "dynamodb:index:WriteCapacityUnits"
+      ServiceNamespace: dynamodb
+
+  PharmacyIndexIncPostDatedScalingWritePolicy:
+    Type: AWS::ApplicationAutoScaling::ScalingPolicy
+    Condition: EnableDynamoDBAutoScalingCondition
+    Properties:
+      PolicyName: PharmacyIndexIncPostDatedWriteScalingPolicy
+      PolicyType: TargetTrackingScaling
+      ScalingTargetId: !Ref PharmacyIndexIncPostDatedScalingWriteTarget
+      TargetTrackingScalingPolicyConfiguration:
+        TargetValue: 50
+        ScaleInCooldown: 600
+        ScaleOutCooldown: 0
+        PredefinedMetricSpecification:
+          PredefinedMetricType: DynamoDBWriteCapacityUtilization
+
+  PharmacyIndexIncPostDatedScalingReadTarget:
+    Type: AWS::ApplicationAutoScaling::ScalableTarget
+    Condition: EnableDynamoDBAutoScalingCondition
+    Properties:
+      MaxCapacity: 100
+      MinCapacity: 1
+      ResourceId: !Sub table/${PrescriptionStatusUpdatesTable}/index/PharmacyODSCodePrescriptionIDIndexIncPostDated
+      RoleARN: !GetAtt DynamoDbScalingRole.Arn
+      ScalableDimension: "dynamodb:index:ReadCapacityUnits"
+      ServiceNamespace: dynamodb
+
+  PharmacyIndexIncPostDatedScalingReadPolicy:
+    Type: AWS::ApplicationAutoScaling::ScalingPolicy
+    Condition: EnableDynamoDBAutoScalingCondition
+    Properties:
+      PolicyName: PharmacyIndexIncPostDatedReadScalingPolicy
+      PolicyType: TargetTrackingScaling
+      ScalingTargetId: !Ref PharmacyIndexIncPostDatedScalingReadTarget
+      TargetTrackingScalingPolicyConfiguration:
+        TargetValue: 70
+        ScaleInCooldown: 600
+        ScaleOutCooldown: 10
+        PredefinedMetricSpecification:
+          PredefinedMetricType: DynamoDBReadCapacityUtilization
+
   NHSNumberIndexScalingWriteTarget:
     Type: AWS::ApplicationAutoScaling::ScalableTarget
     Condition: EnableDynamoDBAutoScalingCondition