diff --git a/.gitignore b/.gitignore
index 10cf122..1edea84 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,7 @@
 *.tsbuildinfo
 /.coverage
 /.db
+/.ethstatedb*
 /.nyc_output
 /.test-data
 /bin
diff --git a/README.md b/README.md
index 324ed73..694f567 100644
--- a/README.md
+++ b/README.md
@@ -77,3 +77,7 @@ COMMANDS
   help     display help for ethstatedb
 ```
 <!-- commandsstop -->
+
+# More information
+1. When playing with data generated by geth, make sure to stop geth so that it flushes all data to database. This command by default copies the data to a temp location, i.e. `.ethstatedb`, to avoid messing up the original database. However, you can use `--skip-copy` to use original database. 
+2. To get stateRoot, use `geth attach ipc://path/to/geth.ipc` to connect to a node. Then use `eth.getBlock(eth.blockNumber).stateRoot` to get stateRoot for the latest block. You can change `eth.blockNumber` to be any one.
\ No newline at end of file
diff --git a/package.json b/package.json
index f5daa0a..0240f35 100644
--- a/package.json
+++ b/package.json
@@ -85,12 +85,11 @@
     "lines": 90,
     "statements": 90,
     "functions": 90,
-    "branches": 50,
+    "branches": 55,
     "reporter": [
       "lcov",
       "text",
-      "text-summary",
-      "cobertura"
+      "text-summary"
     ],
     "report-dir": ".coverage",
     "exclude": [
diff --git a/src/commands/account.ts b/src/commands/account.ts
index c7332c0..fa2c23c 100644
--- a/src/commands/account.ts
+++ b/src/commands/account.ts
@@ -2,6 +2,7 @@ import {Command, flags} from '@oclif/command'
 import cli from 'cli-ux'
 import EAccount from 'ethereumjs-account'
 import {BN, KECCAK256_NULL_S, KECCAK256_RLP_S} from 'ethereumjs-util'
+import * as fs from 'fs-extra'
 
 export default class Account extends Command {
   static description = 'load information of an account'
@@ -23,6 +24,15 @@ export default class Account extends Command {
       required: true,
       description: 'value of stateRoot',
     }),
+    'skip-copy': flags.boolean({
+      required: false,
+      description:
+        'skip copying database to .ethstatedb. By default, database is copied to avoid messing the original database.',
+    }),
+    'work-dir': flags.string({
+      required: false,
+      description: 'directory to pull down database',
+    }),
   }
 
   static args = [
@@ -39,7 +49,15 @@ export default class Account extends Command {
     const level = require('level')
 
     const {args, flags} = this.parse(Account)
-    const db = level(flags.dbdir)
+
+    let workDir = flags.dbdir
+    if (!flags['skip-copy']) {
+      workDir = flags['work-dir'] || '.ethstatedb'
+      await fs.emptyDir(workDir)
+      await fs.copy(flags.dbdir, workDir)
+    }
+
+    const db = level(workDir)
     const trie = new Trie(db, flags.root)
 
     const found = await new Promise((resolve, reject) => {
diff --git a/test/commands/account.test.ts b/test/commands/account.test.ts
index f9951d0..72bf4d0 100644
--- a/test/commands/account.test.ts
+++ b/test/commands/account.test.ts
@@ -1,34 +1,65 @@
 import {expect, test} from '@oclif/test'
+import * as fs from 'fs-extra'
 import * as os from 'os'
 
-import {BlockChainConfig, runBlockchain, SupportedHardforkType} from '../utils/run-blockchain'
+import {runBlockchain, SupportedHardforkType} from '../utils/run-blockchain'
 
 const testData = require('../fixtures/test-blockchain-data.json')
 
-const testOnEthereum = test.register('runEVM', (config: BlockChainConfig) => {
-  return {
-    async run(ctx: any) {
-      ctx.evm = await runBlockchain(config)
-    }
-  }
-})
-
 describe('account', () => {
-  testOnEthereum
-    .runEVM({dbPath: '.db/chaindata',
+  before(async () => {
+    const evm = await runBlockchain({
+      dbPath: '.db/chaindata',
       cachePath: '.db/cachedata',
       validate: true,
       data: testData,
       hardfork: SupportedHardforkType.byzantium,
-      reset: true})
+      reset: true
+    })
+  
+    await new Promise((resolve, reject) => {
+      evm.blockchain.db.close((err: Error, result: any) => {
+        if (err) reject(err)
+  
+        resolve(result)
+      })
+    })
+  })
+
+  test
+    .stdout()
+    .do(() => {
+      fs.copySync('.db/chaindata', '.db/chaindata-1')
+    })
+    .command(['account',
+      '--dbdir', '.db/chaindata-1',
+      '--root', '0xecc60e00b3fe5ce9f6e1a10e5469764daf51f1fe93c22ec3f9a7583a80357217',
+      '--work-dir', '.ethstatedb-1',
+      '0x095e7baea6a6c7c4c2dfeb977efac326af552d87'])
+    .it('runs account', async ctx => {
+      const result: any = {}
+      ctx.stdout.split(os.EOL).map((element: string) => {
+        const tokens = element.trim().split(/\s+/)
+        if (tokens.length > 1) {
+          result[tokens[0]] = tokens[1]
+        }
+      })
+
+      expect(result.Balance).to.equal('10')
+    })
+
+  test
     .stdout()
-    .do(ctx => {
-      ctx.evm.blockchain.db.close()
+    .do(() => {
+      fs.copySync('.db/chaindata', '.db/chaindata-2')
+      fs.removeSync('.ethstatedb')
     })
     .command(['account',
-      '--dbdir', '.db/chaindata',
-      '--root', '0xecc60e00b3fe5ce9f6e1a10e5469764daf51f1fe93c22ec3f9a7583a80357217', '0x095e7baea6a6c7c4c2dfeb977efac326af552d87'])
-    .it('runs account', ctx => {
+      '--dbdir', '.db/chaindata-2',
+      '--root', '0xecc60e00b3fe5ce9f6e1a10e5469764daf51f1fe93c22ec3f9a7583a80357217',
+      '--skip-copy',
+      '0x095e7baea6a6c7c4c2dfeb977efac326af552d87'])
+    .it('runs account --skip-copy', async ctx => {
       const result: any = {}
       ctx.stdout.split(os.EOL).map((element: string) => {
         const tokens = element.trim().split(/\s+/)
@@ -38,5 +69,6 @@ describe('account', () => {
       })
 
       expect(result.Balance).to.equal('10')
+      expect(await fs.pathExists('.ethstatedb')).to.be.false
     })
 })
diff --git a/test/utils/run-blockchain.ts b/test/utils/run-blockchain.ts
index 12eb37f..514cefa 100644
--- a/test/utils/run-blockchain.ts
+++ b/test/utils/run-blockchain.ts
@@ -1,10 +1,10 @@
 import Account from 'ethereumjs-account'
 import * as ethereumUtil from 'ethereumjs-util'
+import * as fs from 'fs-extra'
 import leveldown from 'leveldown'
 import levelup from 'levelup'
 import * as util from 'util'
 
-const fs = require('fs-extra')
 const ethjsUtil = require('ethjs-util')
 const Trie = require('merkle-patricia-tree/secure')
 const Block = require('ethereumjs-block')