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SQL Server insert if not exists best practice
...sert Competitors where doesn't already exist":
INSERT Competitors (cName)
SELECT DISTINCT Name
FROM CompResults cr
WHERE
NOT EXISTS (SELECT * FROM Competitors c
WHERE cr.Name = c.cName)
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Effect of NOLOCK hint in SELECT statements
...
1) Yes, a select with NOLOCK will complete faster than a normal select.
2) Yes, a select with NOLOCK will allow other queries against the effected table to complete faster than a normal select.
Why would this be?
NOLOCK typically (...
How do I search an SQL Server database for a string?
...T)
INSERT INTO @Temp(TableName,SchemaName, ColumnName, DataType)
SELECT C.Table_Name,C.TABLE_SCHEMA, C.Column_Name, C.Data_Type
FROM Information_Schema.Columns AS C
INNER Join Information_Schema.Tables AS T
ON C.Table_Name = T.Table_Name
AND C.TA...
Only read selected columns
...from the data.table-package:
You can specify the desired columns with the select parameter from fread from the data.table package. You can specify the columns with a vector of column names or column numbers.
For the example dataset:
library(data.table)
dat <- fread("data.txt", select = c("Year...
OnChange event handler for radio button (INPUT type=“radio”) doesn't work as one value
...ame attribute myRadios to read the variable prev which holds the currently selected radio. A comparison is done within each click handler to decide if the clicked radio is the same as the one stored in prev and if not then the currently clicked radio is stored there. Within the click handler, you ha...
Get contentEditable caret index position
...tion(editableDiv) {
var caretPos = 0,
sel, range;
if (window.getSelection) {
sel = window.getSelection();
if (sel.rangeCount) {
range = sel.getRangeAt(0);
if (range.commonAncestorContainer.parentNode == editableDiv) {
caretPos = range.endOffset;
}
...
SELECT DISTINCT on one column
...ou're on SQL Server 2005 or greater, you can use a CTE with ROW_NUMBER():
SELECT *
FROM (SELECT ID, SKU, Product,
ROW_NUMBER() OVER (PARTITION BY PRODUCT ORDER BY ID) AS RowNumber
FROM MyTable
WHERE SKU LIKE 'FOO%') AS a
WHERE a.RowNumber = 1
...
PHP code to convert a MySQL query to CSV [closed]
...
SELECT * INTO OUTFILE "c:/mydata.csv"
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY "\n"
FROM my_table;
(the documentation for this is here: http://dev.mysql.com/doc/refman/5.0/en/select.html)
or:...
UITableView Cell selected Color?
...f the cell other than the default [blue color] values for highlighting the selection of cell.
I use this code but nothing happens:
...
How does MySQL process ORDER BY and LIMIT in a query?
...e LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements).
With two arguments, the first argument specifies the offset of the first ...