本文整理汇总了Golang中github.com/cockroachdb/cockroach/sql/sqlwire.Datum类的典型用法代码示例。如果您正苦于以下问题：Golang Datum类的具体用法？Golang Datum怎么用？Golang Datum使用的例子？那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。
在下文中一共展示了Datum类的3个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Golang代码示例。
示例1: unmarshalValue
func unmarshalValue(col structured.ColumnDescriptor, kv client.KeyValue) sqlwire.Datum {
var d sqlwire.Datum
if !kv.Exists() {
return d
}
switch col.Type.Kind {
case structured.ColumnType_BIT, structured.ColumnType_INT:
tmp := kv.ValueInt()
d.IntVal = &tmp
case structured.ColumnType_FLOAT:
tmp := math.Float64frombits(uint64(kv.ValueInt()))
d.FloatVal = &tmp
case structured.ColumnType_CHAR, structured.ColumnType_TEXT,
structured.ColumnType_BLOB:
// TODO(pmattis): The conversion to string isn't strictly necessary, but
// makes log messages more readable right now.
tmp := string(kv.ValueBytes())
d.StringVal = &tmp
}
return d
}示例2: prepareBinaryArgs
// Prepare the arguments for a binary operation. The returned arguments will
// have the same type. The typ parameter specifies the allowed types for the
// operation. For example, bit-operations should specify intOp or uintOp to
// indicate that they do not operate on floating point arguments. Float
// operations may still reduce to intOp or uintOp if the operands support it.
func prepareBinaryArgs(typ opType, left, right sqlwire.Datum) (opType, sqlwire.Datum, sqlwire.Datum, error) {
var err error
switch typ {
case intOp, uintOp:
if left.UintVal != nil || right.UintVal != nil {
left, err = left.ToUint()
if err != nil {
return uintOp, null, null, err
}
right, err = right.ToUint()
if err != nil {
return uintOp, null, null, err
}
return uintOp, left, right, nil
}
left, err = left.ToInt()
if err != nil {
return intOp, null, null, err
}
right, err = right.ToInt()
if err != nil {
return intOp, null, null, err
}
return intOp, left, right, nil
case floatOp:
if (left.UintVal != nil && (right.IntVal != nil || right.UintVal != nil)) ||
(right.UintVal != nil && (left.IntVal != nil || left.UintVal != nil)) {
left, err = left.ToUint()
if err != nil {
return uintOp, null, null, err
}
right, err = right.ToUint()
if err != nil {
return uintOp, null, null, err
}
return uintOp, left, right, nil
}
if left.IntVal != nil && right.IntVal != nil {
return intOp, left, right, nil
}
}
left, err = left.ToFloat()
if err != nil {
return floatOp, null, null, err
}
right, err = right.ToFloat()
if err != nil {
return floatOp, null, null, err
}
return floatOp, left, right, nil
}示例3: prepareComparisonArgs
// Prepare the arguments for a comparison operation. The returned arguments
// will have the same type.
func prepareComparisonArgs(left, right sqlwire.Datum) (opType, sqlwire.Datum, sqlwire.Datum, error) {
// If both arguments are strings (or string-like), compare as strings.
if (left.BytesVal != nil || left.StringVal != nil) &&
(right.BytesVal != nil || right.StringVal != nil) {
return stringOp, left.ToString(), right.ToString(), nil
}
// If both arguments are uints, compare as unsigned.
if left.UintVal != nil && right.UintVal != nil {
return uintOp, left, right, nil
}
var err error
// If both arguments are integers (signed or unsigned), compare as integers.
if (left.BoolVal != nil || left.IntVal != nil || left.UintVal != nil) &&
(right.BoolVal != nil || right.IntVal != nil || right.UintVal != nil) {
left, err = left.ToInt()
if err != nil {
return intOp, null, null, err
}
right, err = right.ToInt()
if err != nil {
return intOp, null, null, err
}
return intOp, left, right, nil
}
// In all other cases, compare as floats.
left, err = left.ToFloat()
if err != nil {
return intOp, null, null, err
}
right, err = right.ToFloat()
if err != nil {
return intOp, null, null, err
}
return floatOp, left, right, nil
}