diff --git a/packages/server/src/api/controllers/query/index.ts b/packages/server/src/api/controllers/query/index.ts
index b9a69f3988..472c0d6272 100644
--- a/packages/server/src/api/controllers/query/index.ts
+++ b/packages/server/src/api/controllers/query/index.ts
@@ -9,7 +9,7 @@ import { quotas } from "@budibase/pro"
 import { events, context, utils, constants } from "@budibase/backend-core"
 import sdk from "../../../sdk"
 import { QueryEvent } from "../../../threads/definitions"
-import { Query } from "@budibase/types"
+import { ConfigType, Query, UserCtx } from "@budibase/types"
 import { ValidQueryNameRegex } from "@budibase/shared-core"
 
 const Runner = new Thread(ThreadType.QUERY, {
@@ -28,11 +28,11 @@ function enrichQueries(input: any) {
   return wasArray ? queries : queries[0]
 }
 
-export async function fetch(ctx: any) {
+export async function fetch(ctx: UserCtx) {
   ctx.body = await sdk.queries.fetch()
 }
 
-const _import = async (ctx: any) => {
+const _import = async (ctx: UserCtx) => {
   const body = ctx.request.body
   const data = body.data
 
@@ -73,7 +73,7 @@ const _import = async (ctx: any) => {
 }
 export { _import as import }
 
-export async function save(ctx: any) {
+export async function save(ctx: UserCtx) {
   const db = context.getAppDB()
   const query = ctx.request.body
 
@@ -100,19 +100,19 @@ export async function save(ctx: any) {
   ctx.message = `Query ${query.name} saved successfully.`
 }
 
-export async function find(ctx: any) {
+export async function find(ctx: UserCtx) {
   const queryId = ctx.params.queryId
   ctx.body = await sdk.queries.find(queryId)
 }
 
 //Required to discern between OIDC OAuth config entries
-function getOAuthConfigCookieId(ctx: any) {
-  if (ctx.user.providerType === constants.Config.OIDC) {
+function getOAuthConfigCookieId(ctx: UserCtx) {
+  if (ctx.user.providerType === ConfigType.OIDC) {
     return utils.getCookie(ctx, constants.Cookie.OIDC_CONFIG)
   }
 }
 
-function getAuthConfig(ctx: any) {
+function getAuthConfig(ctx: UserCtx) {
   const authCookie = utils.getCookie(ctx, constants.Cookie.Auth)
   let authConfigCtx: any = {}
   authConfigCtx["configId"] = getOAuthConfigCookieId(ctx)
@@ -120,7 +120,7 @@ function getAuthConfig(ctx: any) {
   return authConfigCtx
 }
 
-export async function preview(ctx: any) {
+export async function preview(ctx: UserCtx) {
   const { datasource, envVars } = await sdk.datasources.getWithEnvVars(
     ctx.request.body.datasourceId
   )
@@ -129,6 +129,19 @@ export async function preview(ctx: any) {
   // this stops dynamic variables from calling the same query
   const { fields, parameters, queryVerb, transformer, queryId, schema } = query
 
+  let existingSchema = schema
+  if (queryId && !existingSchema) {
+    try {
+      const db = context.getAppDB()
+      const existing = (await db.get(queryId)) as Query
+      existingSchema = existing.schema
+    } catch (err: any) {
+      if (err.status !== 404) {
+        ctx.throw(500, "Unable to retrieve existing query")
+      }
+    }
+  }
+
   const authConfigCtx: any = getAuthConfig(ctx)
 
   try {
@@ -180,6 +193,14 @@ export async function preview(ctx: any) {
         schemaFields[key] = fieldType
       }
     }
+    // if existing schema, update to include any previous schema keys
+    if (existingSchema) {
+      for (let key of Object.keys(schemaFields)) {
+        if (existingSchema[key]?.type) {
+          schemaFields[key] = existingSchema[key].type
+        }
+      }
+    }
     // remove configuration before sending event
     delete datasource.config
     await events.query.previewed(datasource, query)
@@ -189,13 +210,13 @@ export async function preview(ctx: any) {
       info,
       extra,
     }
-  } catch (err) {
+  } catch (err: any) {
     ctx.throw(400, err)
   }
 }
 
 async function execute(
-  ctx: any,
+  ctx: UserCtx,
   opts: any = { rowsOnly: false, isAutomation: false }
 ) {
   const db = context.getAppDB()
@@ -255,17 +276,17 @@ async function execute(
     } else {
       ctx.body = { data: rows, pagination, ...extra, ...info }
     }
-  } catch (err) {
+  } catch (err: any) {
     ctx.throw(400, err)
   }
 }
 
-export async function executeV1(ctx: any) {
+export async function executeV1(ctx: UserCtx) {
   return execute(ctx, { rowsOnly: true, isAutomation: false })
 }
 
 export async function executeV2(
-  ctx: any,
+  ctx: UserCtx,
   { isAutomation }: { isAutomation?: boolean } = {}
 ) {
   return execute(ctx, { rowsOnly: false, isAutomation })
@@ -292,7 +313,7 @@ const removeDynamicVariables = async (queryId: any) => {
   }
 }
 
-export async function destroy(ctx: any) {
+export async function destroy(ctx: UserCtx) {
   const db = context.getAppDB()
   const queryId = ctx.params.queryId
   await removeDynamicVariables(queryId)
diff --git a/packages/server/src/threads/definitions.ts b/packages/server/src/threads/definitions.ts
index dd0891d34a..8915642949 100644
--- a/packages/server/src/threads/definitions.ts
+++ b/packages/server/src/threads/definitions.ts
@@ -11,12 +11,7 @@ export interface QueryEvent {
   queryId: string
   environmentVariables?: Record<string, string>
   ctx?: any
-  schema?: {
-    [key: string]: {
-      name: string
-      type: string
-    }
-  }
+  schema?: Record<string, { name?: string; type: string }>
 }
 
 export interface QueryVariable {
diff --git a/packages/types/src/documents/app/query.ts b/packages/types/src/documents/app/query.ts
index 31a3a3ba09..c288ed9980 100644
--- a/packages/types/src/documents/app/query.ts
+++ b/packages/types/src/documents/app/query.ts
@@ -6,7 +6,7 @@ export interface Query extends Document {
   parameters: QueryParameter[]
   fields: RestQueryFields | any
   transformer: string | null
-  schema: any
+  schema: Record<string, { name?: string; type: string }>
   readable: boolean
   queryVerb: string
 }
diff --git a/packages/types/src/sdk/koa.ts b/packages/types/src/sdk/koa.ts
index 861f5e9329..a7df701171 100644
--- a/packages/types/src/sdk/koa.ts
+++ b/packages/types/src/sdk/koa.ts
@@ -1,5 +1,5 @@
 import { Context, Request } from "koa"
-import { User, Role, UserRoles, Account } from "../documents"
+import { User, Role, UserRoles, Account, ConfigType } from "../documents"
 import { FeatureFlag, License } from "../sdk"
 import { Files } from "formidable"
 
@@ -13,6 +13,7 @@ export interface ContextUser extends Omit<User, "roles"> {
   csrfToken?: string
   featureFlags?: FeatureFlag[]
   accountPortalAccess?: boolean
+  providerType?: ConfigType
   account?: Account
 }