比较函数和运算符Graph

运算符	描述
=	赋值运算符
/	除法运算符
==	等于运算符
!=	不等于运算符
<	小于运算符
<=	小于或等于运算符
-	减法运算符
%	余数运算符
+	加法运算符
*	乘法运算符
-	负号运算符
udf_is_in()	比较函数，判断值是否在指定的列表中

比较运算的结果是 true 或 false 。

• ==

等于。String的比较大小写敏感。不同类的值不相同：

nebula> YIELD 'A' == 'a';
==============
| ("A"=="a") |
==============
| false      |
--------------

nebula> YIELD '2' == 2;
[ERROR (-8)]: A string type can not be compared with a non-string type.

• >

大于：

nebula> YIELD 3 > 2;
=========
| (3>2) |
=========
| true  |
---------

• ≥

大于或等于：

nebula> YIELD 2 >= 2;
==========
| (2>=2) |
==========
| true   |
----------

• <

小于：

nebula> YIELD 2.0 < 1.9;
=========================================
| (2.000000000000000<1.900000000000000) |
=========================================
| false                                 |
-----------------------------------------

• ≤

小于或等于：

nebula> YIELD 0.11 <= 0.11;
========================
| (0.110000<=0.110000) |
========================
| true                 |
------------------------

• !=

不等于：

nebula> YIELD 1 != '1';
[ERROR (-8)]: A string type can not be compared with a non-string type.

• udf_is_in()

第一个参数为要比较的值。

nebula> YIELD udf_is_in(1,0,1,2);
======================
| udf_is_in(1,0,1,2) |
======================
| true               |
----------------------

nebula> GO FROM 100 OVER follow WHERE udf_is_in($$.player.name, "Tony Parker"); /*由于udf_is_in 后面可能变更，所以该示例可能失效。*/
===============
| follow._dst |
===============
| 101         |
---------------

nebula> GO FROM 100 OVER follow YIELD follow._dst AS id | GO FROM $-.id OVER follow WHERE udf_is_in($-.id, 102, 102 + 1);
===============
| follow._dst |
===============
| 100         |
---------------
| 101         |
---------------

---

最后更新: May 12, 2020