re = /(.*),(.*),(.*),(.*)/
str = ',UBS154754528,A121215441,10
,UBS154754528,A121215442,20
,UBS154754528,A121215443,15
GFdfgdfD45454dfgd5457,UBS154754528,A121215444,25
AAA454545455,UBS154754528,A121215445,254
vvGFD454545457,UBS154754528,A121215446,215
dad454545457,UBS154754528,A121215447,55
eww454545457,UBS154754528,A121215448,214
asd454545457,UBS154754528,A121215449,26
trtr454545457,UBS154754528,A121215450,25
,UBS154754528,A121215451,251
,UBS154754528,A121215452,252
,UBS154754528,A121215453,23
,UBS154754528,A121215454,251
gdfgd454545457,UBS154754528,A121215455,251
dfdf454545457,UBS154754528,A121215456,25
fgdfgd454545457,UBS154754528,A121215457,95
gdfgFD45dfg4545457,UBS154754528,A121215458,58
dfgdf4545fg45457,UBS154754528,A121215459,254
dfgd45454dfgfd5457,UBS154754528,A121215460,25
dfdfGFD45dfgdf4545457,UBS154754528,A121215461,254
,UBS154754528,A121215462,66
,UBS154754528,A121215463,22
,UBS154754528,A121215464,54
GfdfgD454fd545457,UBS154754528,A121215465,24
GFfdgD454dfg545457,UBS154754528,A121215466,45
GFfdgD45454fgd5457,UBS154754528,A121215467,11
fgfD4545dfg45457,UBS154754528,A121215468,255
GFfdgD454dfgd545457,UBS154754528,A121215469,88
'
subst = 'insert into test_table values(\'$1\',\'$2\',\'$3\',$4);'
result = str.gsub(re, subst)
# Print the result of the substitution
puts result
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html