Thanks for your reply!

but dispatch table seems not to shorten code. I still have to write a_query,b_query,c_query... respectly. In my brain, a_query_builder, b_query_builder ... and x_query_builder sub are all much similar like: 
sub a_query_builder{
my ($table_name, $display_cols_ref, $where_cols_ref) = @_;

if ($where_cols_ref->{'year_min'})     { push @clauses, "Year >= $wher
+e_cols_ref->{'year_min'}" }
if ($where_cols_ref->{'year_max'})     { push @clauses, "Year <= $wher
+e_cols_ref->{'year_max'}" }

# ...
$clause = join(" AND ", @clauses);
$display_cols = join(",", @$display_cols_ref);
$sth = $dbh->prepare("SELECT $display_cols FROM $table_name WHERE $cla
+use");
}

[download]

I'm not sure the above treatment correct or not, but I hope to create a general code to handle all kinds of query statement building. Is creating a query class a good idea?



I am trying to improve my English skills, if you see a mistake please feel free to reply or /msg me a correction

In reply to Re^2: How treat query elegantly and more? by xiaoyafeng
in thread How treat query elegantly and more? by xiaoyafeng

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