diff --git a/.github/workflows/bun-test.yml b/.github/workflows/bun-test.yml
index 7eaefa8..ada3918 100644
--- a/.github/workflows/bun-test.yml
+++ b/.github/workflows/bun-test.yml
@@ -9,7 +9,6 @@ on:
 jobs:
   bun-test:
     runs-on: ubuntu-latest
-    environment: dev-test
     steps:
       - name: Checkout
         uses: actions/checkout@v3
@@ -21,23 +20,7 @@ jobs:
         run: |
           bun install
 
-      - name: 'Setup local Clickhouse DB'
-        uses: metrico/clickhouse-server-action@v1.0.0
-
-      - name: 'Insert mock data into Clickhouse DB for testing'
-        run: |
-          curl https://clickhouse.com/ | sh
-          echo "CREATE TABLE IF NOT EXISTS block (block_id FixedString(64),block_number UInt32(),chain LowCardinality(String),timestamp DateTime64(3, 'UTC'),final_block Bool) ENGINE = ReplacingMergeTree PRIMARY KEY (block_id) ORDER BY (block_id, block_number, timestamp); INSERT INTO block (*) VALUES ('054d891671caf4978a4cfc3a13fe323d72cd805c215a14a16ea7417d5add3098', 18394250, 'mainnet', '2023-10-20 21:34:47.000', true) ,('167189cd0f77aa5320806a7150c73cbfc97dfd4418c089ecc33511fca48eb0d6', 18394255, 'testnet', '2023-10-20 21:35:47.000', true) ,('1df538c839f821a20b075dfb35ed6f266435190b99276a6651866407ecdd787e', 18394257, 'mainnet', '2023-10-20 21:36:11.000', false) ,('2b225df082189b69727ef443985edaae23c9edcb172fc3f1a37e17071cb2f827', 18394256, 'testnet', '2023-10-20 21:35:59.000', true) ,('34348c1ae22f33a404ec4ba5fbbe513d0da93172bce483f59ef749a465f50eaf', 18394249, 'mainnet', '2023-10-20 21:34:35.000', false);" > setup.sql
-          ./clickhouse client --queries-file ./setup.sql
-
       - name: 'Run test'
         run: |
           bun pretest
           bun test
-        env:
-          HOSTNAME: ${{ vars.HOSTNAME }}
-          PORT: ${{ vars.PORT }}
-          DB_HOST: ${{ vars.DB_HOST }}
-          DB_NAME: ${{ secrets.DB_NAME }}
-          DB_USERNAME: ${{ secrets.DB_USERNAME }}
-          DB_PASSWORD: ''
diff --git a/src/fetch/openapi.ts b/src/fetch/openapi.ts
index dbdc721..2b03bcd 100644
--- a/src/fetch/openapi.ts
+++ b/src/fetch/openapi.ts
@@ -14,7 +14,7 @@ const TAGS = {
   DOCS: "Documentation",
 } as const;
 
-const chains = await supportedChainsQuery();
+export const chains = await supportedChainsQuery();
 const block_example = (await makeQuery(await getBlock( new URLSearchParams({limit: "2"})))).data;
 
 const timestampSchema: SchemaObject = { anyOf: [
diff --git a/src/queries.spec.ts b/src/queries.spec.ts
index 07f889c..7762f3f 100644
--- a/src/queries.spec.ts
+++ b/src/queries.spec.ts
@@ -1,5 +1,6 @@
 import { expect, test } from "bun:test";
 import { getBlock, getChain } from "./queries.js";
+import { chains } from './fetch/openapi.js';
 
 test("getBlock", () => {
     expect(getBlock(new URLSearchParams({ chain: "eth", block_number: "123" })))
@@ -7,6 +8,12 @@ test("getBlock", () => {
 
     expect(getBlock(new URLSearchParams({ chain: "eth", greater_or_equals_by_timestamp: '1438270048', less_or_equals_by_timestamp: '1438270083', limit: '3' })))
         .toBe(`SELECT * FROM blocks WHERE (toUnixTimestamp(timestamp) >= 1438270048 AND toUnixTimestamp(timestamp) <= 1438270083 AND chain == 'eth') ORDER BY block_number DESC LIMIT 3`);
+
+    // Check that if not chain parameter is passed, all chains are included in the selection
+    chains.forEach((chain) => {
+        expect(getBlock(new URLSearchParams({ block_number: "123" })))
+        .toContain(`SELECT * FROM blocks WHERE (chain == '${chain}' AND block_number == '123') ORDER BY block_number DESC LIMIT 1`);
+    });
 });
 
 test("getChain", () => {
diff --git a/src/queries.ts b/src/queries.ts
index 1bcb53a..2d3f665 100644
--- a/src/queries.ts
+++ b/src/queries.ts
@@ -1,5 +1,6 @@
 import { DEFAULT_SORT_BY, config } from './config.js';
 import { parseBlockId, parseLimit, parseTimestamp } from './utils.js';
+import { chains } from './fetch/openapi.js';
 
 export interface Block {
     block_number: number;
@@ -11,44 +12,60 @@ export interface Block {
 export function getBlock(searchParams: URLSearchParams) {
     // TO-DO: Modulo block number (ex: search by every 1M blocks)
 
-    // SQL Query
-    let query = `SELECT * FROM ${config.table}`;
-    const where = [];
-
-    // Clickhouse Operators
-    // https://clickhouse.com/docs/en/sql-reference/operators
-    const operators = [
-        ["greater_or_equals", ">="],
-        ["greater", ">"],
-        ["less_or_equals", "<="],
-        ["less", "<"],
-    ]
-    for ( const [key, operator] of operators ) {
-        const block_number = searchParams.get(`${key}_by_block_number`);
-        const timestamp = parseTimestamp(searchParams.get(`${key}_by_timestamp`));
-        if (block_number) where.push(`block_number ${operator} ${block_number}`);
-        if (timestamp) where.push(`toUnixTimestamp(timestamp) ${operator} ${timestamp}`);
-    }
+    let createBlockQuery = (searchParams: URLSearchParams) => {
+        // SQL Query
+        let query = `SELECT * FROM ${config.table}`;
+        const where = [];
+
+        // Clickhouse Operators
+        // https://clickhouse.com/docs/en/sql-reference/operators
+        const operators = [
+            ["greater_or_equals", ">="],
+            ["greater", ">"],
+            ["less_or_equals", "<="],
+            ["less", "<"],
+        ]
+        for ( const [key, operator] of operators ) {
+            const block_number = searchParams.get(`${key}_by_block_number`);
+            const timestamp = parseTimestamp(searchParams.get(`${key}_by_timestamp`));
+            if (block_number) where.push(`block_number ${operator} ${block_number}`);
+            if (timestamp) where.push(`toUnixTimestamp(timestamp) ${operator} ${timestamp}`);
+        }
+
+        // equals
+        const chain = searchParams.get("chain");
+        const block_id = parseBlockId(searchParams.get("block_id"));
+        const block_number = searchParams.get('block_number');
+        const timestamp = parseTimestamp(searchParams.get('timestamp'));
+        if (chain) where.push(`chain == '${chain}'`);
+        if (block_id) where.push(`block_id == '${block_id}'`);
+        if (block_number) where.push(`block_number == '${block_number}'`);
+        if (timestamp) where.push(`toUnixTimestamp(timestamp) == ${timestamp}`);
+
+        // Join WHERE statements with AND
+        if ( where.length ) query += ` WHERE (${where.join(' AND ')})`;
+
+        // Sort and Limit
+        const limit = parseLimit(searchParams.get("limit"));
+        const sort_by = searchParams.get("sort_by");
+        query += ` ORDER BY block_number ${sort_by ?? DEFAULT_SORT_BY}`
+        query += ` LIMIT ${limit}`
+
+        return query;
+    };
 
-    // equals
     const chain = searchParams.get("chain");
-    const block_id = parseBlockId(searchParams.get("block_id"));
-    const block_number = searchParams.get('block_number');
-    const timestamp = parseTimestamp(searchParams.get('timestamp'));
-    if (chain) where.push(`chain == '${chain}'`);
-    if (block_id) where.push(`block_id == '${block_id}'`);
-    if (block_number) where.push(`block_number == '${block_number}'`);
-    if (timestamp) where.push(`toUnixTimestamp(timestamp) == ${timestamp}`);
-
-    // Join WHERE statements with AND
-    if ( where.length ) query += ` WHERE (${where.join(' AND ')})`;
-
-    // Sort and Limit
-    const limit = parseLimit(searchParams.get("limit"));
-    const sort_by = searchParams.get("sort_by");
-    query += ` ORDER BY block_number ${sort_by ?? DEFAULT_SORT_BY}`
-    query += ` LIMIT ${limit}`
-    return query;
+
+    if (!chain) {
+        let queries = chains.map((chain) => {
+            searchParams.set('chain', chain);
+            return createBlockQuery(searchParams);
+        });
+
+        return queries.join(' UNION ALL ');
+    } else {
+        return createBlockQuery(searchParams);
+    }
 }
 
 export function getChain() {