Map decision functions

Map decision functions/operators perform a judgment on the input map data and return a Boolean value. seekdb currently supports the = and != operators.

=/!=

The = and != operators determine whether two map data are equal. The syntax is as follows:

map1 = map2;
map1 != map2;

The input parameters are described as follows:

• map1 must be a map type.
• map2 must be a map type.

The returned results are described as follows:

• For =, 1 indicates equality, and 0 indicates inequality.
• For !=, 0 indicates equality, and 1 indicates inequality.
• Two maps are considered equal only when their keys and values are all equal.

Here are some examples:

SELECT map(1,"a",2,"b") = map(1,"a",2,"b");
+-------------------------------------+
| map(1,"a",2,"b") = map(1,"a",2,"b") |
+-------------------------------------+
|                                   1 |
+-------------------------------------+
1 row in set (0.001 sec)

-- When comparing, the system automatically converts arrays to comparable types
SELECT map(1,"a",2,"b") = map("1","a","2","b");
+-----------------------------------------+
| map(1,"a",2,"b") = map("1","a","2","b") |
+-----------------------------------------+
|                                       1 |
+-----------------------------------------+
1 row in set (0.001 sec)

-- When the keys are equal but the values are not, 0 is returned
SELECT map(1,"a",2,"b") = map(1,"a",2,"c");
+-------------------------------------+
| map(1,"a",2,"b") = map(1,"a",2,"c") |
+-------------------------------------+
|                                   0 |
+-------------------------------------+
1 row in set (0.001 sec)