precision, scale, ok := columnType.DecimalSize()
		if ok {
			if !strings.HasPrefix(fullDataType, fmt.Sprintf("%s(%d,%d)", realDataType, precision, scale)) &&
				!strings.HasPrefix(fullDataType, fmt.Sprintf("%s(%d)", realDataType, precision)) {
				alterColumn = true
			}
		}
	} else {
		if precision, _, ok := columnType.DecimalSize(); ok && int64(field.Precision) != precision {

pkg database/sql/driver, type TxOptions struct, ReadOnly bool
pkg database/sql, func Named(string, interface{}) NamedArg
pkg database/sql, method (*ColumnType) DatabaseTypeName() string
pkg database/sql, method (*ColumnType) DecimalSize() (int64, int64, bool)
pkg database/sql, method (*ColumnType) Length() (int64, bool)
pkg database/sql, method (*ColumnType) Name() string
pkg database/sql, method (*ColumnType) Nullable() (bool, bool)