// Encodes datum at the end of key, using direction `dir` for the encoding.
// It takes in an inclusive key and returns an inclusive key if
// isLastEndConstraint is not set, and an exclusive key otherwise (the idea is
// that, for inclusive constraints, the value for the last column in the
// constraint needs to be adapted to an exclusive span.EndKey).
func encodeInclusiveEndValue(
key roachpb.Key, datum parser.Datum, dir encoding.Direction, isLastEndConstraint bool,
) roachpb.Key {
// Since the end of a span is exclusive, if the last constraint is an
// inclusive one, we might need to make the key exclusive by applying a
// PrefixEnd(). We normally avoid doing this by transforming "a = x" to
// "a = x±1" for the last end constraint, depending on the encoding direction
// (since this keeps the key nice and pretty-printable).
// However, we might not be able to do the ±1.
needExclusiveKey := false
if isLastEndConstraint {
if dir == encoding.Ascending {
if datum.IsMax() || !datum.HasNext() {
needExclusiveKey = true
} else {
datum = datum.Next()
}
} else {
if datum.IsMin() || !datum.HasPrev() {
needExclusiveKey = true
} else {
datum = datum.Prev()
}
}
}
key, err := sqlbase.EncodeTableKey(key, datum, dir)
if err != nil {
panic(err)
}
if needExclusiveKey {
key = key.PrefixEnd()
}
return key
}
func checkKeyCount(t *testing.T, kvDB *client.DB, prefix roachpb.Key, numKeys int) {
if kvs, err := kvDB.Scan(context.TODO(), prefix, prefix.PrefixEnd(), 0); err != nil {
t.Fatal(err)
} else if l := numKeys; len(kvs) != l {
t.Fatalf("expected %d key value pairs, but got %d", l, len(kvs))
}
}
// TODO(dt): Batch checks of many rows.
func (f baseFKHelper) check(values parser.DTuple) (parser.DTuple, error) {
var key roachpb.Key
if values != nil {
keyBytes, _, err := sqlbase.EncodeIndexKey(
f.searchTable, f.searchIdx, f.ids, values, f.searchPrefix)
if err != nil {
return nil, err
}
key = roachpb.Key(keyBytes)
} else {
key = roachpb.Key(f.searchPrefix)
}
spans := roachpb.Spans{roachpb.Span{Key: key, EndKey: key.PrefixEnd()}}
if err := f.rf.StartScan(f.txn, spans, true /* limit batches */, 1); err != nil {
return nil, err
}
return f.rf.NextRowDecoded()
}