SQL

sql not null

SELECT column_name FROM table_name 
WHERE column_name IS NOT NULL;

sql is not null

SELECT * FROM my_table WHERE my_column IS NOT NULL;

SQL NOT NULL Constraint

CREATE TABLE Colleges (
  college_id INT NOT NULL,
  college_code VARCHAR(20),
  college_name VARCHAR(50)
);

SQL IS NULL and IS NOT NULL

SELECT *
FROM Employee
WHERE email IS NULL;

NOT NULL SQL

By default, a column can hold NULL values.
The NOT NULL constraint enforces a column to NOT accept NULL values.
This enforces a field to always contain a value, which means that you cannot insert a new record, or update a record without adding a value to this field.

Sql NOT NULL in creating a table
CREATE TABLE Persons (
    ID int NOT NULL,
    LastName varchar(255) NOT NULL,
    FirstName varchar(255) NOT NULL,
    Age int
);

SQL NOT NULL Constraint

CREATE TABLE Persons (
    ID int NOT NULL,
    LastName varchar(255) NOT NULL,
    FirstName varchar(255) NOT NULL,
    Age int
);

sql is not null

The reverse of NULL. Tests for values that aren’t empty / NULL
"Tests for empty (NULL) values.
Example: Returns users that haven’t given a contact number.
SELECT * FROM users
WHERE contact_number IS NULL;"

is not null sql

select c_custkey, c_name, c_address from customer where c_custkey in (select o_orderkey from orders where o_orderkey IS NOT NULL)

SQL NOT NULL Constraint

CREATE TABLE Colleges (
  college_id INT NOT NULL,
  college_code VARCHAR(20) NOT NULL,
  college_name VARCHAR(50)
);

not null

Response
{
  "result": [
    {
      "id": "<RULE_ID_1>",
      "paused": false,
      "description": "allow API traffic without challenge",
      "action": "allow",
      "priority": true,
      "filter": {
        "id": "<FILTER_ID_1>",
        "expression": "http.request.uri.path matches "^/api/.*$"",
        "paused": false,
        "description": "/api"
      }
    },
    {
      "id": "<RULE_ID_2>",
      "paused": false,
      "description": "do not challenge login from office",
      "action": "allow",
      "priority": null,
      "filter": {
        "id": "<FILTER_ID_2>",
        "expression": "ip.src in {2400:cb00::/32 2803:f800::/32 2c0f:f248::/32 2a06:98c0::/29} and (http.request.uri.path ~ "^.*/wp-login.php$" or http.request.uri.path ~ "^.*/xmlrpc.php$")",
        "paused": false,
        "description": "Login from office"
      }
    },
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      "id": "<RULE_ID_3>",
      "paused": false,
      "description": "challenge login",
      "action": "challenge",
      "priority": true,
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        "id": "<FILTER_ID_3>",
        "expression": "(http.request.uri.path ~ "^.*/wp-login.php$" or http.request.uri.path ~ "^.*/xmlrpc.php$")",
        "paused": false,
        "description": "Login"
      }
    },
    {
      "id": "<RULE_ID_4>",
      "paused": false,
      "description": "JS challenge site",
      "action": "js_challenge",
      "priority": null,
      "filter": {
        "id": "<FILTER_ID_4>",
        "expression": "not http.request.uri.path matches "^/api/.*$"",
        "paused": false,
        "description": "not /api"
      }
    }
  ],
  "success": true,
  "errors": [],
  "messages": [],
  "result_info": {
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