How to filter a df with startswith() in a field?

question
data

#1

Nor these two approach works:

df = DataFrame(field1 = ["abc", "abb", "acc"])
pattern   = "ab"
ps = sizeof(pattern)
filteredDf = myData[df[:field1][1:ps] .== pattern), :] 
filteredDf = myData[startswith(df[:field1],pattern), :]

#2

my error… this works (Julia 0.6):

filteredDf = df[startswith.(df[:field1],pattern),:]