MySQL 5.6

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create table extable (id int auto_increment primary key,
network text)
insert into extable (network) values (' {
   "Interface_1":{
      "Caption":"[00000004] Intel(R) Dual Band Wireless-AC 3160",
      "MACAddress":"D0:7E:35:D3:C1:52",
      "DHCPServer":"192.168.1.1",
      "IPAddress":"192.168.1.101",
      "DNSServerSearchOrder":[
         "8.8.8.8",
         "9.9.9.9"
      ],
      "DefaultIPGateway":"192.168.1.1",
      "IPSubnet":"255.255.255.0"
   },
   "Interface_2":{
      "Caption":"[00000011] VMware Virtual Ethernet Adapter for VMnet1",
      "MACAddress":"00:50:56:C0:00:01",
      "IPAddress":[
         "192.168.29.1",
         "fe80::d9f4:2bfa:59f:b9ba"
      ],
      "IPSubnet":[
         "255.255.255.0",
         "64"
      ]
   },
   "Interface_3":{
      "Caption":"[00000013] VMware Virtual Ethernet Adapter for VMnet8",
      "MACAddress":"00:50:56:C0:00:08",
      "IPAddress":[
         "192.168.71.1",
         "fe80::acec:db96:af3a:4680"
      ],
      "IPSubnet":[
         "255.255.255.0",
         "64"
      ]
   }
}')
SELECT * FROM `extable` 
WHERE network RLIKE '"MACAddress":"[[:<:]]00:50:56:C0:00:08[[:>:]]"'


id
network


1
 {
   "Interface_1":{
      "Caption":"[00000004] Intel(R) Dual Band Wireless-AC 3160",
      "MACAddress":"D0:7E:35:D3:C1:52",
      "DHCPServer":"192.168.1.1",
      "IPAddress":"192.168.1.101",
      "DNSServerSearchOrder":[
         "8.8.8.8",
         "9.9.9.9"
      ],
      "DefaultIPGateway":"192.168.1.1",
      "IPSubnet":"255.255.255.0"
   },
   "Interface_2":{
      "Caption":"[00000011] VMware Virtual Ethernet Adapter for VMnet1",
      "MACAddress":"00:50:56:C0:00:01",
      "IPAddress":[
         "192.168.29.1",
         "fe80::d9f4:2bfa:59f:b9ba"
      ],
      "IPSubnet":[
         "255.255.255.0",
         "64"
      ]
   },
   "Interface_3":{
      "Caption":"[00000013] VMware Virtual Ethernet Adapter for VMnet8",
      "MACAddress":"00:50:56:C0:00:08",
      "IPAddress":[
         "192.168.71.1",
         "fe80::acec:db96:af3a:4680"
      ],
      "IPSubnet":[
         "255.255.255.0",
         "64"
      ]
   }
}


SELECT * FROM `extable` 
WHERE network RLIKE '"Interface_1":{[^}]*"MACAddress":"[[:<:]]00:50:56:C0:00:08[[:>:]]"'


id
network


SELECT * FROM `extable` 
WHERE network RLIKE '"Interface_3":{[^}]*"MACAddress":"[[:<:]]00:50:56:C0:00:08[[:>:]]"'


id
network


1
 {
   "Interface_1":{
      "Caption":"[00000004] Intel(R) Dual Band Wireless-AC 3160",
      "MACAddress":"D0:7E:35:D3:C1:52",
      "DHCPServer":"192.168.1.1",
      "IPAddress":"192.168.1.101",
      "DNSServerSearchOrder":[
         "8.8.8.8",
         "9.9.9.9"
      ],
      "DefaultIPGateway":"192.168.1.1",
      "IPSubnet":"255.255.255.0"
   },
   "Interface_2":{
      "Caption":"[00000011] VMware Virtual Ethernet Adapter for VMnet1",
      "MACAddress":"00:50:56:C0:00:01",
      "IPAddress":[
         "192.168.29.1",
         "fe80::d9f4:2bfa:59f:b9ba"
      ],
      "IPSubnet":[
         "255.255.255.0",
         "64"
      ]
   },
   "Interface_3":{
      "Caption":"[00000013] VMware Virtual Ethernet Adapter for VMnet8",
      "MACAddress":"00:50:56:C0:00:08",
      "IPAddress":[
         "192.168.71.1",
         "fe80::acec:db96:af3a:4680"
      ],
      "IPSubnet":[
         "255.255.255.0",
         "64"
      ]
   }
}