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What is the fastest way to compute sin and cos together?
...are supported on processor level, I expect them to be way much faster than table lookups.
Edit:
Wikipedia suggests that FSINCOS was added at 387 processors, so you can hardly find a processor which doesn't support it.
Edit:
Intel's documentation states that FSINCOS is just about 5 times slower tha...
CSS table column autowidth
...
Works perfectly! (my case having table width 100% and no other columns have widths. Applied this to one column). Tested in IE7/8/9, Firefox 12 and Chrome 19.
– marcovtwout
Jun 20 '12 at 14:12
...
Possible to perform cross-database queries with PostgreSQL?
...them.
postgres_fdw
Use postgres_fdw (foreign data wrapper) to connect to tables in any Postgres database - local or remote.
Note that there are foreign data wrappers for other popular data sources. At this time, only postgres_fdw and file_fdw are part of the official Postgres distribution.
For P...
How to check if a column exists in a SQL Server table?
...HERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tableName', 'columnName') IS NOT NULL
BEGIN
-- Column Exists
END
...
Solutions for INSERT OR UPDATE on SQL Server
Assume a table structure of MyTable(KEY, datafield1, datafield2...) .
22 Answers
22
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How to do an update + join in PostgreSQL?
...ATE syntax is:
[ WITH [ RECURSIVE ] with_query [, ...] ]
UPDATE [ ONLY ] table [ [ AS ] alias ]
SET { column = { expression | DEFAULT } |
( column [, ...] ) = ( { expression | DEFAULT } [, ...] ) } [, ...]
[ FROM from_list ]
[ WHERE condition | WHERE CURRENT OF cursor_name ]
...
Efficient SQL test query or validation query that will work across all (or most) databases
...ostgreSQL
SQLite
SELECT 1 FROM DUAL
Oracle
SELECT 1 FROM any_existing_table WHERE 1=0
or
SELECT 1 FROM INFORMATION_SCHEMA.SYSTEM_USERS
or
CALL NOW()
HSQLDB (tested with version 1.8.0.10)
Note: I tried using a WHERE 1=0 clause on the second query, but it didn't work as a value for Apache Commo...
SQL Server loop - how do I loop through a set of records
...EGIN
SET @MyCursor = CURSOR FOR
select top 1000 YourField from dbo.table
where StatusID = 7
OPEN @MyCursor
FETCH NEXT FROM @MyCursor
INTO @MyField
WHILE @@FETCH_STATUS = 0
BEGIN
/*
YOUR ALGORITHM GOES HERE
*/
FETCH NEXT FROM...
How can I add a column that doesn't allow nulls in a Postgresql database?
...
You have to set a default value.
ALTER TABLE mytable ADD COLUMN mycolumn character varying(50) NOT NULL DEFAULT 'foo';
... some work (set real values as you want)...
ALTER TABLE mytable ALTER COLUMN mycolumn DROP DEFAULT;
...
Proper REST response for empty table?
...nt to get list of users by calling GET to api/users , but currently the table was truncated so there are no users. What is the proper response for this scenario: 404 or 204 ?
...