SQL Queries

To count number of columns in a Table
The INFORMATION_SCHEMA COLUMNS Table
Sntax :
SELECT COLUMN_NAME, DATA_TYPE, IS_NULLABLE, COLUMN_DEFAULT
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_name = 'tbl_name'
[AND table_schema = 'db_name']
[AND column_name LIKE 'wild']

SHOW COLUMNS
FROM tbl_name
[FROM db_name]
[LIKE 'wild']
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Example:
SELECT COUNT(*)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_name = 'mrc_tav'
AND table_schema = 'noon_test'
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To display all the table names in Database
Syntax:
SHOW TABLES [FROM database_name]