add --where helper for select queries

Now we can add some basic filtering when using the query helpers.

Refs #136

bin/ysql

@@ -110,6 +110,10 @@ Instead of C<SELECT * FROM person>, we can use the C<--select> helper:
 
     $ ysql db_name --select person
 
+And we can combine it with the C<--where> helper:
+
+    $ ysql db_name --select person --where 'dept = "Science"'
+
 And for simple inserts, we can use the C<--insert> helper:
 
     # input.yml
@@ -150,6 +154,10 @@ Generate an C<INSERT INTO table ( fields ) VALUES ( values )> query for the
 given C<table>. For each document read on STDIN, the correct fields and values
 will be used.
 
+=head2 --where <clause>
+
+Add a C<WHERE> clause to a C<--select> query.
+
 =head2 --config
 
 View, add, and edit database configuration.

lib/ETL/Yertl/Command/ysql.pm

@@ -35,6 +35,7 @@ sub main {
         'edit|e=s',
         'select=s',
         'insert=s',
+        'where=s',
     );
     #; use Data::Dumper;
     #; say Dumper \@args;
@@ -199,7 +200,7 @@ sub main {
         # Other queries that do not require special handling
         my $query;
         if ( $opt{select} ) {
-            $query = $sql->select( $opt{select} );
+            $query = $sql->select( $opt{select}, '*', $opt{where} );
         }
         else {
             $query = shift @args;

t/bin/ysql.t

@@ -517,6 +517,24 @@ subtest 'query' => sub {
                     email => '[email protected]',
                 },
             );
+
+            subtest '--where' => sub {
+                my ( $stdout, $stderr, $exit ) = capture {
+                    ysql->main( 'testdb', '--select', 'person', '--where', 'id >= 2' );
+                };
+                is $exit, 0;
+                ok !$stderr, 'nothing on stderr' or diag $stderr;
+
+                open my $fh, '<', \$stdout;
+                my $yaml_fmt = ETL::Yertl::Format::yaml->new( input => $fh );
+                cmp_deeply [ $yaml_fmt->read ], bag(
+                    {
+                        id => 2,
+                        name => 'Quentin Quinn',
+                        email => '[email protected]',
+                    },
+                );
+            };
         };
 
         subtest '--insert' => sub {