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Linq: What is the difference between Select and Where
The Select and Where methods are available in Linq. What should every developer know about these two methods? For example: when to use one over the other, any advantages of using one over the other, etc.
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SQL: How to properly check if a record exists
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It's better to use either of the following:
-- Method 1.
SELECT 1
FROM table_name
WHERE unique_key = value;
-- Method 2.
SELECT COUNT(1)
FROM table_name
WHERE unique_key = value;
The first alternative should give you no result or one result, the second count should be zero or on...
How to use `string.startsWith()` method ignoring the case?
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One option is to convert both of them to either lowercase or uppercase:
"Session".toLowerCase().startsWith("sEsSi".toLowerCase());
This is wrong. See: https://stackoverflow.com/a/15518878/14731
Another option is to use String#regionMat...
'IF' in 'SELECT' statement - choose output value based on column values
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SELECT id,
IF(type = 'P', amount, amount * -1) as amount
FROM report
See http://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of...
Is there any difference between GROUP BY and DISTINCT
...CT and distinct by UNION cause an oracle error, but GROUP BY worked; I was selecting only 1 column from a view and not using any aggregation; I'm still baffled why it required it, but it does confirm there is some difference in the execution. As others point out, it also lets you GROUP BY columns no...
month name to month number and vice versa in python
I am trying to create a function that can convert a month number to an abbreviated month name or an abbreviated month name to a month number. I thought this might be a common question but I could not find it online.
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Insert all values of a table into another table in SQL
.... But the insert statement accepts values, but i would like it to accept a select * from the initial_Table. Is this possible?
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PhpStorm wrap/surround selection?
... to wrap a certain part of text. Is there any shortcut to wrap the current selection, for example:
4 Answers
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Adding options to a using jQuery?
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This did NOT work in IE8 (yet did in FF):
$("#selectList").append(new Option("option text", "value"));
This DID work:
var o = new Option("option text", "value");
/// jquerify the DOM object 'o' so we can use the html method
$(o).html("option text");
$("#selectList").a...
Search all tables, all columns for a specific value SQL Server [duplicate]
...NULL
BEGIN
SET @ColumnName = ''
SET @TableName =
(
SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABL...