diff --git a/.cspell.json b/.cspell.json
index a9f7279..f52f75d 100644
--- a/.cspell.json
+++ b/.cspell.json
@@ -26,6 +26,7 @@
     "Galactica",
     "gjuchault",
     "Goyer",
+    "granularities",
     "graphlib",
     "hler",
     "ilike",
diff --git a/src/__tests__/index.test.ts b/src/__tests__/index.test.ts
index 1a9f7f4..5da0afc 100644
--- a/src/__tests__/index.test.ts
+++ b/src/__tests__/index.test.ts
@@ -94,7 +94,7 @@ await describe("semantic layer", async () => {
         sql: ({ model }) => model.column("CustomerId"),
       })
       .withDimension("invoice_date", {
-        type: "date",
+        type: "datetime",
         sql: ({ model }) => model.column("InvoiceDate"),
       })
       .withMetric("total", {
@@ -522,6 +522,56 @@ await describe("semantic layer", async () => {
         { customers___customer_id: 1, albums___title: "Use Your Illusion I" },
       ]);
     });
+
+    await it("can correctly query datetime granularities", async () => {
+      const query = queryBuilder.buildQuery({
+        dimensions: [
+          "invoices.invoice_id",
+          "invoices.invoice_date",
+          "invoices.invoice_date.time",
+          "invoices.invoice_date.date",
+          "invoices.invoice_date.year",
+          "invoices.invoice_date.quarter",
+          "invoices.invoice_date.quarter_of_year",
+          "invoices.invoice_date.month",
+          "invoices.invoice_date.month_num",
+          "invoices.invoice_date.week",
+          "invoices.invoice_date.week_num",
+          "invoices.invoice_date.day_of_month",
+          "invoices.invoice_date.hour",
+          "invoices.invoice_date.hour_of_day",
+          "invoices.invoice_date.minute",
+        ],
+        filters: [
+          { operator: "equals", member: "invoices.invoice_id", value: [6] },
+        ],
+      });
+
+      const result = await client.query<InferSqlQueryResultType<typeof query>>(
+        query.sql,
+        query.bindings,
+      );
+
+      assert.deepEqual(result.rows, [
+        {
+          invoices___invoice_date: new Date("2009-01-18T23:00:00.000Z"),
+          invoices___invoice_date___date: new Date("2009-01-18T23:00:00.000Z"),
+          invoices___invoice_date___day_of_month: 19,
+          invoices___invoice_date___hour: "2009-01-19 0",
+          invoices___invoice_date___hour_of_day: 0,
+          invoices___invoice_date___minute: "2009-01-19 0:0",
+          invoices___invoice_date___month: "2009-1",
+          invoices___invoice_date___month_num: 1,
+          invoices___invoice_date___quarter: "2009-Q1",
+          invoices___invoice_date___quarter_of_year: 1,
+          invoices___invoice_date___time: "00:00:00",
+          invoices___invoice_date___week: "2009-W4",
+          invoices___invoice_date___week_num: 4,
+          invoices___invoice_date___year: 2009,
+          invoices___invoice_id: 6,
+        },
+      ]);
+    });
   });
 
   await describe("models from sql queries", async () => {
diff --git a/src/lib/dialect/base.ts b/src/lib/dialect/base.ts
index c689ed1..8789f2c 100644
--- a/src/lib/dialect/base.ts
+++ b/src/lib/dialect/base.ts
@@ -3,22 +3,33 @@ import { Granularity } from "../types.js";
 export class BaseDialect {
   withGranularity(granularity: Granularity, sql: string) {
     switch (granularity) {
-      case "day":
-        return `EXTRACT(DAY FROM ${sql})`;
-      case "week":
-        return `EXTRACT(WEEK FROM ${sql})`;
-      case "month":
-        return `EXTRACT(MONTH FROM ${sql})`;
-      case "quarter":
-        return `EXTRACT(QUARTER FROM ${sql})`;
+      case "time":
+        return `CAST(${sql} AS TIME)`;
+      case "date":
+        return `CAST(${sql} AS DATE)`;
       case "year":
         return `EXTRACT(YEAR FROM ${sql})`;
+      case "quarter":
+        return `EXTRACT(YEAR FROM ${sql}) || '-' || 'Q' || EXTRACT(QUARTER FROM ${sql})`;
+      case "quarter_of_year":
+        return `EXTRACT(QUARTER FROM ${sql})`;
+      case "month":
+        return `EXTRACT (YEAR FROM ${sql}) || '-' || EXTRACT(MONTH FROM ${sql})`;
+      case "month_num":
+        return `EXTRACT(MONTH FROM ${sql})`;
+      case "week":
+        return `EXTRACT (YEAR FROM ${sql}) || '-' || 'W' || EXTRACT(WEEK FROM ${sql})`;
+      case "week_num":
+        return `EXTRACT(WEEK FROM ${sql})`;
+      case "day_of_month":
+        return `EXTRACT(DAY FROM ${sql})`;
       case "hour":
+        return `CAST(${sql} AS DATE) || ' ' || EXTRACT(HOUR FROM ${sql})`;
+      case "hour_of_day":
         return `EXTRACT(HOUR FROM ${sql})`;
       case "minute":
-        return `EXTRACT(MINUTE FROM ${sql})`;
-      case "second":
-        return `EXTRACT(SECOND FROM ${sql})`;
+        return `CAST(${sql} AS DATE) || ' ' || EXTRACT(HOUR FROM ${sql}) || ':' || EXTRACT(MINUTE FROM ${sql})`;
+
       default:
         // biome-ignore lint/correctness/noSwitchDeclarations: Exhaustiveness check
         const _exhaustiveCheck: never = granularity;
diff --git a/src/lib/model.ts b/src/lib/model.ts
index a088eb5..1e61436 100644
--- a/src/lib/model.ts
+++ b/src/lib/model.ts
@@ -1,6 +1,8 @@
 import {
+  DimensionWithGranularity,
   Granularity,
   GranularityByDimensionType,
+  GranularityIndex,
   MemberFormat,
   MemberNameToType,
   MemberType,
@@ -114,9 +116,7 @@ export type WithGranularityDimensions<
   N extends string,
   T extends string,
 > = T extends keyof GranularityByDimensionType
-  ? { [k in N]: T } & {
-      [k in `${N}.${GranularityByDimensionType[T][number]}`]: number;
-    }
+  ? { [k in N]: T } & DimensionWithGranularity<N, T>
   : { [k in N]: T };
 
 export interface DimensionProps<C, DN extends string = string> {
@@ -310,7 +310,11 @@ export class Model<
         this.dimensions[`${name}.${g}`] = new Dimension(
           this,
           `${name}.${g}`,
-          { ...dimension, type: "number" },
+          {
+            ...dimension,
+            type: GranularityIndex[g].type,
+            description: GranularityIndex[g].description,
+          },
           g,
         );
       }
diff --git a/src/lib/types.ts b/src/lib/types.ts
index 77930a8..b1c4267 100644
--- a/src/lib/types.ts
+++ b/src/lib/types.ts
@@ -57,26 +57,122 @@ export interface SqlWithBindings {
   bindings: unknown[];
 }
 
+export const GranularityIndex = {
+  time: {
+    description: "Time of underlying field. Example output: 00:00:00",
+    type: "time",
+  },
+  date: {
+    description: "Date of underlying field. Example output: 2021-01-01",
+    type: "date",
+  },
+  year: {
+    description: "Year of underlying field. Example output: 2021",
+    type: "number",
+  },
+  quarter: {
+    description: "Quarter of underlying field. Example output: 2021-Q1",
+    type: "string",
+  },
+  quarter_of_year: {
+    description: "Quarter of year of underlying field. Example output: 1",
+    type: "number",
+  },
+  month: {
+    description: "Month of underlying field. Example output: 2021-01",
+    type: "string",
+  },
+  month_num: {
+    description: "Month number of underlying field. Example output: 1",
+    type: "number",
+  },
+  week: {
+    description: "Week of underlying field. Example output: 2021-W01",
+    type: "string",
+  },
+  week_num: {
+    description: "Week number of underlying field. Example output: 1",
+    type: "number",
+  },
+  day_of_month: {
+    description: "Day of month of underlying field. Example output: 1",
+    type: "number",
+  },
+  hour: {
+    description:
+      "Datetime of the underlying field truncated to the hour. Example output: 2021-01-01 00",
+    type: "string",
+  },
+  hour_of_day: {
+    description: "Hour of underlying field. Example output: 00",
+    type: "string",
+  },
+  minute: {
+    description:
+      "Datetime of the underlying field truncated to the minute. Example output: 2021-01-01 00:00",
+    type: "string",
+  },
+} as const satisfies Record<string, { description: string; type: MemberType }>;
+
+export type GranularityIndex = typeof GranularityIndex;
+
+export type GranularityToMemberType = {
+  [K in keyof GranularityIndex]: GranularityIndex[K]["type"];
+};
+
+function granularities<T extends (keyof GranularityIndex)[]>(
+  ...granularities: T
+): T[number][] {
+  return granularities;
+}
+
 export const GranularityByDimensionType = {
-  time: ["hour", "minute", "second"],
-  date: ["year", "quarter", "month", "week", "day"],
-  datetime: [
+  time: granularities("hour", "hour_of_day", "minute"),
+  date: granularities(
     "year",
     "quarter",
+    "quarter_of_year",
     "month",
+    "month_num",
     "week",
-    "day",
+    "week_num",
+    "day_of_month",
+  ),
+  datetime: granularities(
+    "time",
+    "date",
+    "year",
+    "quarter",
+    "quarter_of_year",
+    "month",
+    "month_num",
+    "week",
+    "week_num",
+    "day_of_month",
     "hour",
+    "hour_of_day",
     "minute",
-    "second",
-  ],
+  ),
 } as const;
 
 export type GranularityByDimensionType = typeof GranularityByDimensionType;
-export type Granularity =
-  GranularityByDimensionType[keyof GranularityByDimensionType][number];
+export type Granularity = keyof typeof GranularityIndex;
+
+export type DimensionWithGranularity<
+  D extends string,
+  T extends keyof GranularityByDimensionType,
+  GT extends keyof GranularityIndex = GranularityByDimensionType[T][number],
+> = {
+  [K in GT as `${D}.${K}`]: GranularityToMemberType[K];
+};
 
-export type MemberType = "string" | "number" | "date" | "datetime" | "boolean";
+export type MemberType =
+  | "string"
+  | "number"
+  | "date"
+  | "datetime"
+  | "time"
+  | "boolean";
 export type MemberFormat = "percentage" | "currency";
 
 export type MemberNameToType = { [k in never]: MemberType };
@@ -86,14 +182,19 @@ export type QueryReturnType<
   N extends keyof M,
   S = Pick<M, N>,
 > = {
-  [K in keyof S as Replace<string & K, ".", "___">]: S[K] extends "string"
+  [K in keyof S as Replace<
+    string & K,
+    ".",
+    "___",
+    { all: true }
+  >]: S[K] extends "string"
     ? string
     : S[K] extends "number"
       ? number
       : S[K] extends "date"
         ? Date
         : S[K] extends "time"
-          ? Date
+          ? string
           : S[K] extends "datetime"
             ? Date
             : S[K] extends "boolean"
@@ -102,7 +203,7 @@ export type QueryReturnType<
 };
 
 export type ProcessTOverridesNames<T extends Record<string, unknown>> = {
-  [K in keyof T as Replace<string & K, ".", "___">]: T[K];
+  [K in keyof T as Replace<string & K, ".", "___", { all: true }>]: T[K];
 };
 
 // biome-ignore lint/correctness/noUnusedVariables: We need the RT generic param to be present so we can extract it to infer the return type later