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java.sql.SQLException: - ORA-01000: maximum open cursors exceeded
... a query, specifically the position where a reader is in a ResultSet. Each SELECT statement has a cursor, and PL/SQL stored procedures can open and use as many cursors as they require. You can find out more about cursors on Orafaq.
A database instance typically serves several different schemas, man...
ORACLE 常用日期函数 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...的日期。如果给出一负数，返回值日期之前几个月日期。select add_months(to_date(&...ADD_MONTHS函数在输入日期上加上指定的几个月返回一个新的日期。如果给出一负数，返回值日期之前几个月日期。
select add_months(to_date('20150201','yyyymmd...
Select distinct values from a table field
...tart with the fields in
distinct(), in the same order.
For example, SELECT DISTINCT ON (a) gives you the first row for each
value in column a. If you don’t specify an order, you’ll get some
arbitrary row.
If you want to e-g- extract a list of cities that you know shops in , the exam...
What is a stored procedure?
...
CREATE PROCEDURE Users_GetUserInfo
@login nvarchar(30)=null
AS
SELECT * from [Users]
WHERE ISNULL(@login,login)=login
A benefit of stored procedures is that you can centralize data access logic into a single place that is then easy for DBA's to optimize. Stored procedures also have...
MySQL and GROUP_CONCAT() maximum length
...You should use it like this.
SET SESSION group_concat_max_len = 1000000;
select group_concat(column) from table group by column
You can do this even in sharing hosting, but when you use an other session, you need to repeat the SET SESSION command.
...
Unable to run app in Simulator: Xcode beta 6 iOS 8
...r dialog shows up, you still would have access to the iOS Simulator's menu
Select Hardware > Device > Manage Devices
Click on the little + sign at the bottom
Add (if missing) all the devices that you want, or delete and recreate the ones malfunctioning.
If anyone of the simulator is not workin...
Remove duplicate rows in MySQL
...ate temporary table tmpTable (id int);
insert into tmpTable
(id)
select id
from YourTable yt
where exists
(
select *
from YourTabe yt2
where yt2.title = yt.title
and yt2.company = yt.company
and yt2.site_id = yt.si...
Trigger change() event when setting 's value with val() function
... easiest and best way to trigger change event when setting the value of select element.
5 Answers
...
Get table name by constraint name [duplicate]
...
SELECT owner, table_name
FROM dba_constraints
WHERE constraint_name = <<your constraint name>>
will give you the name of the table. If you don't have access to the DBA_CONSTRAINTS view, ALL_CONSTRAINTS or US...
How to Get True Size of MySQL Database?
... would like to know how much space does my MySQL database use, in order to select a web host.
I found the command SHOW TABLE STATUS LIKE 'table_name' so when I do the query, I get something like this:
...