Get database schema with one query?

Question

Basically I want to get the table names, and the field names for each table from the current database that is connected, nothing else.

Is this possible?

I know that SHOW TABLES FROM my_database gets you the table names, and SHOW COLUMNS FROM my_table will get you the fields, but that's at least [1 x # of tables] queries and I get more information that I want :)

Answer 1

The INFORMATION_SCHEMA.COLUMNS table has what you're asking for.

SELECT table_name, column_name
    FROM INFORMATION_SCHEMA.COLUMNS
    WHERE table_schema = 'YourDBName'
    ORDER BY table_name, ordinal_position

Answer 2

SELECT * 
FROM information_schema.tables t
JOIN information_schema.columns c ON t.TABLE_NAME = c.TABLE_NAME 
 AND t.TABLE_CATALOG=c.TABLE_CATALOG 
 AND t.TABLE_SCHEMA=c.TABLE_SCHEMA

works for SQLSERVER 2005. The column names might be different for MySQL (I assume that's what you're using), but the concept is the same.

Answer 3

SELECT t.name AS tblName,
SCHEMA_NAME(schema_id) AS [schemaName],
c.name AS colName
FROM sys.tables AS t
INNER JOIN sys.columns c ON t.OBJECT_ID = c.OBJECT_ID
ORDER BY tblName;

Answer 4

"Show databases", "Show tables" and "describe table" are the best, fastest way I know of in MySql.

But they are MySql-specific.

If you want:

a) a portable way to query your database schema

 ... AND ...

b) more granular control over your query, then look at INFORMATION_SCHEMA:

http://dev.mysql.com/doc/refman/5.0/en/information-schema.html

SYNTAX:

SELECT table_name FROM INFORMATION_SCHEMA.TABLES
  WHERE table_schema = 'db_name'
  [AND table_name LIKE 'wild']

Answer 5

After a few trials, i made this sql code to see the columns in my table.

SELECT 
TABLE_NAME as table_name, 
COLUMN_NAME as column_name, 
COLUMN_TYPE as data_type, 
COLUMN_DEFAULT as default_value, 
IS_NULLABLE as nullable,
COLUMN_KEY as constraints, 
EXTRA as constraints2, 
CHARACTER_SET_NAME as charset, 
COLLATION_NAME as collation 
FROM INFORMATION_SCHEMA.COLUMNS 
WHERE table_schema = '<YOUR_DATABASE_NAME>' 
AND TABLE_NAME='<YOUR_TABLE_NAME>' 
ORDER BY table_name, ordinal_position