If specific columns match, add them to the same row using BASH - awk

Question

I have data that looks like this:
client1 5 10 12 17
client1 6 8 3 20
client1 3 2 2 2
client2 3 3 3 3
client2 4 4 0 0
client2 0 3 3 9
...
client100 3 3 2 1
client100 1 1 1 2
client100 3 3 4 4
I want to make it so there is only one row for every client, with all the information of each client row, merged into one. So for example, client1 and client2 would look like this merged (but obviously I need all the clients merged.)
client1 5 10 12 17 6 8 3 20 3 2 2 2
client2 3 3 3 3 4 4 0 0 0 3 3 9
awk '{ x[$1]=x[$1] " " $2; y[$2]=y[$2] " " $1; }
END {
for (k in x) print k,x[k] >"OUTPUT1";
for (k in y) print k,y[k] >"OUTPUT2";
}' INPUT

Answer 1

When you're merging, you need to add all the fields, not just field 2. The easiest way to do this is to empty field 1, then append the whole record to the array entry.
awk '{ client = $1; $1 = ""; x[client] = x[client] $0 }
END { for (k in x) print k x[k] }' INPUT
I'm not sure what your array y was for. There doesn't seem to be any reason for an array that uses the second field as the keys.

Answer 2

Could you please try following. This should provide output in same order in which $1 has occurred in Input_file.
awk '
{
gsub(/\r/,"")
}
!a[$1]++{
b[++count]=$1
}
{
val=$1
$1=""
sub(/^ +/,"")
c[val]=(c[val]?c[val] OFS:"")$0
}
END{
for(i=1;i<=count;i++){
print b[i],c[b[i]]
}
}
' Input_file
Explanation: Adding detailed explanation for above code.
awk ' ##Starting awk program.
{
gsub(/\r/,"")
}
!a[$1]++{ ##Checking condition if $1 is NOT in array a then do following.
b[++count]=$1 ##Creating array b with index count and value is $1.
}
{
val=$1 ##Creating a variable val whose value is $1.
$1="" ##Nullifying $1 here.
sub(/^ +/,"") ##Substituting initial space with null here.
c[val]=(c[val]?c[val] OFS:"")$0 ##Creating an array c whose index is variable val and value is complete line value and its concatenating its own value each time cursor comes here.
}
END{
for(i=1;i<=count;i++){ ##Starting a for loop from i=1 till value of count here.
print b[i],c[b[i]] ##Printing value of array b with index i and array c with index of b[i].
}
}
' Input_file ##Mentioning Input_fie name here.