Running promises sequentially. Reading and writing data is done asynchronously. There will be a sequence of read write processes, in which each process is determined from the preceding process. If sourceData is written by some process, next process should not write again.

sequentialPromises.js

const sourceData = []

const readData = () => new Promise(res => {
  setTimeout(() => res(sourceData), 500)
})

const writeData = (data) => new Promise(res => {
  setTimeout(() => {
    sourceData.push(data)
    res(sourceData)
  }, 500)
})

const querySelect = (query) => new Promise(res => {
  readData().then(data => res(data))
})

const queryInsert = (data) => new Promise(res => {
  writeData(data).then(newData => res(newData))
})

function test (array) {
  const funcs = array.map((v) => () => new Promise(res => {
    querySelect()
      .then(data => {
        if (data && data.length < 1) {
          queryInsert(v)
            .then(() => res(true))
        } else {
          res(false)
        }
      })
  }))

  return funcs.reduce((promise, func) => 
    promise.then(all => 
      func().then(result => 
        all.concat(result)
      )
    )
  ,Promise.resolve([]))
}

test([1,2,3,4,5])
  .then(finalRes => console.log(finalRes))