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MySQL: Fastest way to count number of rows
...s.
The solution is SQL_CALC_FOUND_ROWS. This is usually used when you are selecting rows but still need to know the total row count (for example, for paging).
When you select data rows, just append the SQL_CALC_FOUND_ROWS keyword after SELECT:
SELECT SQL_CALC_FOUND_ROWS [needed fields or *] FROM t...
How do you check what version of SQL Server for a database using TSQL?
...
Try
SELECT @@VERSION
or for SQL Server 2000 and above the following is easier to parse :)
SELECT SERVERPROPERTY('productversion')
, SERVERPROPERTY('productlevel')
, SERVERPROPERTY('edition')
From: http://support....
SQL Server dynamic PIVOT query?
... @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX);
SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(c.category)
FROM temp c
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set @query = 'SELECT date, ' + @cols + ' from
(...
How to concatenate text from multiple rows into a single text string in SQL server?
...y, John, Sam
2 Alaina, Edward
I used the following T-SQL:
SELECT Main.SubjectID,
LEFT(Main.Students,Len(Main.Students)-1) As "Students"
FROM
(
SELECT DISTINCT ST2.SubjectID,
(
SELECT ST1.StudentName + ',' AS [text()]
FR...
DISTINCT for only one column
...
If you are using SQL Server 2005 or above use this:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ...
How to check if a table exists in a given schema
... whether a table (or view) exists, and the current user has access to it?
SELECT EXISTS (
SELECT FROM information_schema.tables
WHERE table_schema = 'schema_name'
AND table_name = 'table_name'
);
The information schema is mainly useful to stay portable across major versions and...
Removing leading zeroes from a field in a SQL statement
... VARCHAR(10) field. So, for example, if the field contains '00001A', the SELECT statement needs to return the data as '1A'.
...
Include headers when using SELECT INTO OUTFILE?
...
You'd have to hard code those headers yourself. Something like:
SELECT 'ColName1', 'ColName2', 'ColName3'
UNION ALL
SELECT ColName1, ColName2, ColName3
FROM YourTable
INTO OUTFILE '/path/outfile'
share
...
jQuery remove options from select
I have a page with 5 selects that all have a class name 'ct'. I need to remove the option with a value of 'X' from each select while running an onclick event. My code is:
...
What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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