role DBDish::StatementHandle
The Connection C<prepare> method returns a StatementHandle object that
should provides the C<execute> and C<finish> methods.


head

A Statetement handle should provide also the low-level C<_row> and C<_free>
methods.


It also has all the methods from C<DBDish::Role::ErrorHandling>.



need DBDish::ErrorHandling;

unit role DBDish::StatementHandle does DBDish::ErrorHandling;

my role IntTrue { method Bool { self.defined } };

has Int $.Executed = 0;
has Bool $.Finished = True;
has Bool $!disposed = False;
has Int $!affected-rows;
has @!column-name;
has @!column-type;
has $!which = self.WHICH;

# My defined interface
method execute(*@ --> DBDish::StatementHandle) { ... }
method finish(--> Bool) { ... }
method _row(--> Array) { ... }
method _free() { ... }

method !ftr() {
    $.parent.last-sth-id = $!which;
}

method !enter-execute(int $got = 0, int $expect = 0) {
    self.finish unless $!Finished;
    $!affected-rows = Nil;
    self!ftr;
    self!set-err( -1,
            "Wrong number of arguments to method execute: got $got, expected $expect"
        ).fail unless $got == $expect;
}

method !done-execute(Int $rows, $fields) {
    $!Executed++;
    $!Finished = False;
    $!affected-rows = $rows;
    self.finish unless $fields;
    self;
}

method new(*%args) {
    my \sth = ::?CLASS.bless(|%args);
    %args<parent>.register-statement-handle(sth)
}

method dispose() {
    self.finish unless $!Finished;
    self._free;
    $!disposed = True;
    with $.parent.unregister-statement-handle(self) {
        $.parent.last-rows = self.rows;
        True;
    } else { False };
}
#Avoid leaks if explicit dispose isn't used by the user.
submethod DESTROY() {
    self.dispose;
}

method rows() {self._rows}

method _rows {
    my constant TRUE_ZERO = 0 but IntTrue;
    $!affected-rows.defined
            ?? $!affected-rows || TRUE_ZERO
            !! Int;
}

method row(:$hash) {
    self!ftr;
    self!set-err( -1,
            "row() called after Statement Handle disposed."
            ).fail if ($!disposed);

    self!set-err(-1,
            "row() called before execute()"
            ).fail if ($.Executed == 0);

    if my \r = self._row {
        $hash ?? (@!column-name Z=> @(r)).hash !! r.Array;
    } else {
        $hash ?? % !! @;
    }
}

method column-names {
    @!column-name;
}

method column-types {
    @!column-type;
}

multi method allrows(:$array-of-hash!) {
    gather {
        self!set-err( -1,
                "Lazy data used after Statement Handle disposed. Retain statement handle or use allrows(:array-of-hash).eager"
                ).fail if ($!disposed);

        while self.row(:hash) -> %r {
            take %r;
        }
    }
}

multi method allrows(:$hash-of-array!) {
    my %rows = @!column-name Z=> [] xx *;
    while self.row -> @a {
        for @a Z @!column-name -> ($v, $n) {
            %rows{$n}.push: $v;
        }
    }
    %rows;
}

multi method allrows() {
    gather {
        self!set-err( -1,
                "Lazy data used after Statement Handle disposed. Retain statement handle or use allrows().eager"
                ).fail if ($!disposed);

        while self.row -> \r {
            take r;
        }
    }
}

# Legacy
method fetchrow is DEPRECATED('row()') {
    if my \r = self._row {
        my @ = (r.map: { .defined ?? ~$_ !! Str });
    } else { @ };
}

method fetchrow-hash is DEPRECATED('row(:hash)') {
    hash @!column-name Z=> self.fetchrow;
}
method fetchrow_hashref is DEPRECATED('row(:hash)'){ self.fetchrow-hash }

method fetchall_hashref(Str $key) is DEPRECATED('allrows(:hash-of-arrays)') {
    my %results;
    while self.fetch-hash -> \h {
        %results{h{$key}} = h;
    }
    %results;
}

method fetchall-hash is DEPRECATED('allrows(:hash-of-arrays)') {
    my @names := @!column-name;
    my %res = @names Z=> [] xx *;
    for self.fetchall-array -> @a {
        for @a Z @names -> ($v, $n) {
            %res{$n}.push: $v;
        }
    }
    %res;
}

method fetchall-AoH is DEPRECATED('allrows(:array-of-hash)') {
    (0 xx *).flatmap({
        my $h = self.fetchrow-hash;
        last unless $h;
        $h;
    }).eager;
}

method fetchall-array is DEPRECATED('allrows(:array-of-hash)') {
    (0 xx *).flatmap({
        my $r = self.fetchrow;
        last unless $r;
        $r;
    }).eager;
}

method fetchrow_array is DEPRECATED('row(:array)') { self.fetchrow }
method fetchrow_arrayref is DEPRECATED('row(:array)') { self.fetchrow; }
method fetch is DEPRECATED('row()') { self.fetchrow; }

method fetchall_arrayref is DEPRECATED('allrows(:array-of-hash)') { [ self.fetchall-array.eager ] }


root

DBIish

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StatementHandle

role DBDish::StatementHandle The Connection `prepare` method returns a StatementHandle object that should provides the `execute` and `finish` methods.

DBIish v0.6.4

Authors

License

Dependencies

Test Dependencies

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Documentation

role DBDish::StatementHandle The Connection prepare method returns a StatementHandle object that should provides the execute and finish methods.