大约有 47,000 项符合查询结果(耗时:0.0409秒) [XML]

https://stackoverflow.com/ques... 

Adding 'serial' to existing column in Postgres

...int, b text); CREATE TABLE bar (a serial, b text); INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i; INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i; -- blocks of commands to turn foo into bar CREATE SEQUENCE foo_a_seq; ALTER TABLE foo ALTER...
https://stackoverflow.com/ques... 

How can I confirm a database is Oracle & what version it is using SQL?

I'm building an installer for an application. The user gets to select a datasource they have configured and nominate what type of database it is. I want to confirm that the database type is indeed Oracle, and if possible, what version of Oracle they are running by sending a SQL statement to the dat...
https://stackoverflow.com/ques... 

In Ruby, is there an Array method that combines 'select' and 'map'?

... I usually use map and compact together along with my selection criteria as a postfix if. compact gets rid of the nils. jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1} => [3, 3, 3, nil, nil, nil] jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1}.compact => ...
https://stackoverflow.com/ques... 

Inserting data into a temporary table

... INSERT INTO #TempTable (ID, Date, Name) SELECT id, date, name FROM physical_table share | improve this answer | follow | ...
https://stackoverflow.com/ques... 

jquery get all form elements: input, textarea & select

Is there an easy way (without listing them all separately) in jquery to select all form elements and only form elements. 12...
https://stackoverflow.com/ques... 

How to select distinct rows in a datatable and store into an array

...n named ProcessName. This ProcessName contains repeated names.So i want to select only distinct names.Is this possible. 18 ...
https://stackoverflow.com/ques... 

How to get a number of random elements from an array?

...- Math.random()); // Get sub-array of first n elements after shuffled let selected = shuffled.slice(0, n); DEMO: share | improve this answer | follow | ...
https://stackoverflow.com/ques... 

Which are more performant, CTE or temporary tables?

...(A INT IDENTITY PRIMARY KEY, B INT , F CHAR(8000) NULL); INSERT INTO T(B) SELECT TOP (1000000) 0 + CAST(NEWID() AS BINARY(4)) FROM master..spt_values v1, master..spt_values v2; Example 1 WITH CTE1 AS ( SELECT A, ABS(B) AS Abs_B, F FROM T ) SELECT * FROM CTE1 WHERE A = 780 ...
https://stackoverflow.com/ques... 

How to generate the “create table” sql statement for an existing table in postgreSQL

... text; column_record record; BEGIN FOR column_record IN SELECT b.nspname as schema_name, b.relname as table_name, a.attname as column_name, pg_catalog.format_type(a.atttypid, a.atttypmod) as column_type, CASE WHEN ...
https://stackoverflow.com/ques... 

T-SQL: Opposite to string concatenation - how to split string into multiple records [duplicate]

...12)) RETURNS table AS RETURN ( WITH Pieces(pn, start, stop) AS ( SELECT 1, 1, CHARINDEX(@sep, @s) UNION ALL SELECT pn + 1, stop + 1, CHARINDEX(@sep, @s, stop + 1) FROM Pieces WHERE stop > 0 ) SELECT pn, SUBSTRING(@s, start, CASE WHEN stop > 0 THE...