Просторы интернета
Some time ago there was a question on the sql.ru about splitting validity periods for gym cards to enabled and blocked periods:
-- we have a table with gym cards (card id, validity period: from/to) CREATE TABLE cards(id_card NUMBER, num_card VARCHAR2(100), dt_from DATE, dt_to DATE); -- periods when cards were blocked (record id, [...]You may know that table() (kokbf$ collection functions), xmltable and json_table functions block Join-Predicate PushDown(JPPD).
Simple example:
You can see that JPPD works fine in case of global temporary tables and, obviously, the first workaround is to [...]
Today I wanted to give a link to the description of v$sql_hint.target_level to show that no_parallel can be specified for statement or object, and though it's pretty obvious, but surprisingly I haven't found any articles or posts about it, so this short post describes it.
v$sql_hint.target_level is a bitset, where
1st bit [...]
It is quite normal for Oracle database objects to become INVALID, especially when a dependency chain is broken. This articles takes a closer look at:
typical reasons why Oracle objects become INVALID how to identify INVALID objects [...]
Consider a PL/SQL stored procedure that handles a heavy transaction. The procedure is extremely slow – when executed from a UI, the application hangs for minutes. On analysis it is found that the procedure is performing a complex series [...]
When UTL_HTTP web service calls nicely return 2xx status codes, all is well with the world. Things get tricky when a web service call encounters an error and sends back a non-2xx response. [...]
Pagination is the process of dividing query results (typically on a user interface) into discrete pages, where each page contains a smaller/more manageable number of rows. In classic offset pagination, each page shows a fixed count of rows [...]
Pagination is the process of dividing query results (typically on a user interface) into discrete pages, where each page contains a smaller/more manageable number of rows. In classic offset pagination, each page shows a fixed count of rows [...]
When we need to enforce uniqueness on a combination of table columns *only if* a certain condition is true, Oracle helps us implement this using a function-based index.
What is a Function-Based Index?A function-based index is created on the value of [...]
When we need to enforce uniqueness on a combination of table columns *only if* a certain condition is true, Oracle helps us implement this using a function-based index.
What is a Function-Based Index?A function-based index is created on the value of [...]
Some solution requirements are best addressed with Java code in the Oracle database. This article shows you use cases where Java methods in Oracle are useful, how Oracle lets you store Java methods and how they can be called from PL/SQL.
Java [...]Some solution requirements are best addressed with Java code in the Oracle database. This article shows you use cases where Java methods in Oracle are useful, how Oracle lets you store Java methods and how they can be called from SQL [...]
INNER JOIN
Inner join или просто join возвращает только те строки из двух таблиц, которые удовлетворяют условию указанному в ON:
SELECT
s.id,
s.supplier_name,
[...]
INNER JOIN
Inner join или просто join возвращает только те строки из двух таблиц, которые удовлетворяют условию указанному в ON:
SELECT
s.id,
s.supplier_name,
[...]
A typical scenario that involves splitting a comma-separated string into rows:
in a UI-driven query, the user would enter a list of IDs into an input box, and the application should retrieve details for the input list of IDsThe [...]
A typical scenario that involves splitting a comma-separated string into rows:
in a UI-driven query, the user would enter a list of IDs into an input box, and the application should retrieve details for the input list of IDsThe [...]