Determining data types
The columns table of the INFORMATION_SCHEMA database also allows us to extract information about the data types of columns in a table. We can extract information like the character or string length of a CHAR or VARCHAR column or the precision of a DECIMAL or NUMERIC floating point type.
Using the techniques you learned in the lesson, let's explore the customer table of our DVD Rental database.
Questo esercizio fa parte del corso
Functions for Manipulating Data in PostgreSQL
Istruzioni dell'esercizio
- Select the column name and data type from the
INFORMATION_SCHEMA.COLUMNSsystem database. - Limit results to only include the
customertable.
Esercizio pratico interattivo
Prova a risolvere questo esercizio completando il codice di esempio.
-- Get the column name and data type
SELECT
___,
___
-- From the system database information schema
FROM ___.COLUMNS
-- For the customer table
WHERE table_name = ___;