merge.q now generates list of groups of first character syms to group save with in wdb.q, updated wdb.q to handle partition flag partbyfirstchar

Author: ryanCheale

code/common/merge.q

@@ -40,6 +40,10 @@ checkenumerabletype:{[tablename;extrapartitiontype]
 getextrapartitions:{[tablename;extrapartitiontype]
         value each ?[tablename;();1b;extrapartitiontype!extrapartitiontype]
         };
+/ - functional select equivilent to select distinct [ extrapartitiontype ] from [ tablename ] group exec {first each string x} distinct [ extrapartitiontype ] from [ tablename ]
+
+getfirstcharpartitions:{[tablename;extrapartitiontype] raze each value (?[tablename;();();(distinct;first extrapartitiontype)]) group  ?[tablename;();();({first each string x};(distinct;first extrapartitiontype))]};
+
 
 /-function to return partition directory chunks that will be called in batch by mergebypart function
 getpartchunks:{[partdirs;mergelimit]

code/processes/wdb.q

@@ -168,9 +168,7 @@ savetablesbypart:{[dir;pt;forcesave;tablename;writedownmode]
         /- check if provided column extrapartitiontype indeed has an enumerable type in table
         if[writedownmode~`partbyenum;.merge.checkenumerabletype[tablename;extrapartitiontype]];
         /- get list of distinct combinations for partition directories
-        extrapartitions:.merge.getextrapartitions[tablename;extrapartitiontype];
-        if[writedownmode~`partbyfirstchar; 
-            extrapartitions:value extrapartitions group .Q.fu[{first each string x}; extrapartitions:raze extrapartitions]];
+       extrapartitions:$[writedownmode~`partbyfirstchar;.merge.getfirstcharpartitions;.merge.getextrapartitions][tablename;extrapartitiontype];
         /- enumerate data to be upserted
         enumdata:.Q.en[hdbsettings[`hdbdir];0!.save.manipulate[tablename;`. tablename]];
         .lg.o[`save;"enumerated ",(string tablename)," table"];