diff --git a/ft_build/sparksLib/bigqueryIndex.ts b/ft_build/sparksLib/bigqueryIndex.ts
index 339e62da..aff63926 100644
--- a/ft_build/sparksLib/bigqueryIndex.ts
+++ b/ft_build/sparksLib/bigqueryIndex.ts
@@ -75,6 +75,68 @@ const significantDifference = (fieldsToSync, change) => {
   }, false);
 };
 
+const transformToSQLValue = (value: any, ftType: string) => {
+  if (value === null || value === undefined) {
+    return `null`;
+  }
+
+  const sanitise = (x: string) => x?.replace?.(/\"/g, '\\"') ?? "";
+
+  switch (ftType) {
+    case "SIMPLE_TEXT":
+    case "LONG_TEXT":
+    case "EMAIL":
+    case "PHONE_NUMBER":
+    case "CODE":
+    case "RICH_TEXT":
+    case "ID":
+    case "SINGLE_SELECT":
+      // STRING
+      return `"${sanitise(value)}"`;
+    case "JSON":
+    case "FILE":
+    case "IMAGE":
+    case "USER":
+    case "COLOR":
+      // STRING (json representation)
+      if (!value.length) {
+        return `null`;
+      }
+      return `"${sanitise(JSON.stringify(value))}"`;
+    case "MULTI_SELECT":
+      // STRING (array representation, comma separated)
+      return `"${sanitise(value.toString())}"`;
+    case "CHECK_BOX":
+      // BOOLEAN
+      return value ? `true` : `false`;
+    case "NUMBER":
+    case "PERCENTAGE":
+    case "RATING":
+    case "SLIDER":
+      // NUMERIC
+      return Number(value);
+    case "DATE":
+    case "DATE_TIME":
+    case "DURATION":
+      // TIMESTAMP
+      if (!value?.toDate) {
+        return `null`;
+      }
+      return `timestamp("${value.toDate()}")`;
+    case "LAST":
+    case "STATUS":
+    case "SUB_TABLE":
+    case "DOCUMENT_SELECT":
+    case "SERVICE_SELECT":
+    case "ACTION":
+    case "DERIVATIVE":
+    case "AGGREGATE":
+    default:
+      // unknown or meaningless to sync
+      return `null`;
+  }
+};
+
 const bigqueryIndex = async (payload, sparkContext) => {
   const { row, objectID, index, fieldsToSync } = payload;
 
@@ -87,21 +149,6 @@ const bigqueryIndex = async (payload, sparkContext) => {
   const { projectID } = await getSecret("algolia");
   console.log(`projectID: ${projectID}, index: ${index}`);
 
-  // big query specifig helper functions
-  type dataType = Record<string, string>;
-
-  // return keys and values in SQL format
-  // keys: key1,key2,key3
-  // values: "val1","val2","val3"
-  function formatData(data: dataType) {
-    return {
-      keys: Object.keys(data).join(","),
-      values: Object.values(data)
-        .map((value) => `"${value.replace(/\"/g, '\\"')}"`)
-        .join(","),
-    };
-  }
-
   // return if the objectID exists in bool
   async function exist() {
     const query = `SELECT objectID FROM ${index}
@@ -114,7 +161,10 @@ const bigqueryIndex = async (payload, sparkContext) => {
   }
 
   async function insert(data) {
-    const { keys, values } = formatData(data);
+    const keys = Object.keys(data).join(",");
+    const values = Object.keys(data)
+      .map((key) => transformToSQLValue(data[key], fieldTypes[key]))
+      .join(",");
     const query = `INSERT INTO ${index}
     (objectID, ${keys})
     VALUES ("${objectID}", ${values})
@@ -124,11 +174,10 @@ const bigqueryIndex = async (payload, sparkContext) => {
     console.log(res);
   }
 
-  async function update(data: dataType) {
+  async function update(data: Record<string, string>) {
     const keys = Object.keys(data);
-    const values = Object.values(data);
     const dictValues = Array.from(Array(keys.length).keys())
-      .map((i) => `${keys[i]}="${values[i].replace(/\"/g, '\\"')}"`)
+      .map((i) => `${keys[i]}=${transformToSQLValue(data[i], fieldTypes[i])}`)
       .join(",");
     const query = `UPDATE ${index}
           SET ${dictValues}