UPDATE summary_data SET current_category = (SELECT category_id FROM products WHERE products.product_id = summary_data.product_id) WHERE EXISTS (SELECT category_id FROM products WHERE products.product_id = summary_data.product_id); If you want to test your skills using the SQL UPDATE statement, try some of our practice exercises.
ROWID is primarily for values returned by the ROWID pseudocolumn.
Usage Notes In Oracle Lite, the ROWID is the hexadecimal string representing the unique object identifier.
You will be given questions that you need to solve.
After each exercise, we provide the solution so you can check your answer.
Usage Notes When creating a table, you can optionally specify different tablespace and storage characteristics for BLOB columns.
You can initialize a column with the BLOB datatype by inserting an EMPTY_BLOB. BLOB columns contain LOB locators that can refer to out-of-line or in-line LOB values.
When you create a table, you must specify a datatype for each of its columns.
Oracle provides the following categories of built-in datatypes: The character datatypes store character (alphanumeric) data in strings, with byte values corresponding to the character encoding scheme, generally called a character set or code page.
In the current implementation, the precision of a FLOAT is always set to 15.
Examples is the scale of a decimal number (the number of digits to the right of the decimal point). By default, NUMBER data is returned as a character string or SQL_C_CHAR, but conversion into SQL_C_LONG or SQL_C_FLOAT or other datatypes is supported.
The database's character set is established when you create the database.