describe sql query code example

Example 1: sql describe

-- As the name suggests, DESCRIBE is used to describe something. Since in database we have tables, that’s why we use DESCRIBE or DESC(both are same) command to describe the structure of a table.
Syntax:

DESCRIBE one;
  OR
DESC one;
-- Note : We can use either DESCRIBE or DESC(both are Case Insensitive).

-- Suppose our table whose name is one has 3 columns named FIRST_NAME, LAST_NAME and SALARY and all are of can contain null values.

Example 2: select from describe sql

SELECT COLUMN_NAME AS `Field`, COLUMN_TYPE AS `Type`, IS_NULLABLE AS `NULL`, 
       COLUMN_KEY AS `Key`, COLUMN_DEFAULT AS `Default`, EXTRA AS `Extra`
FROM information_schema.COLUMNS  
WHERE TABLE_SCHEMA = 'schemaName' AND TABLE_NAME = 'table1';