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How to change package name of Android Project in Eclipse?
...can rename or change the package name, and also by right-clicking and then select Rename option, you can change or rename the package name.
When you press F2, it will show you the dialog box as:
In this dialog, don't forget to check the "Update references" checkbox because by making "check" to t...
Fast way to discover the row count of a table in PostgreSQL
...in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like this (extremely fast):
SELECT reltuples::bigint AS estimate FROM pg_class where relname='mytable';
How close the estimate is depends on ...
CSS Child vs Descendant selectors
I am a bit confused between these 2 selectors.
8 Answers
8
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MySQL Conditional Insert
...
If your DBMS does not impose limitations on which table you select from when you execute an insert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = ...
MySQL get row position in ORDER BY
...
Use this:
SELECT x.id,
x.position,
x.name
FROM (SELECT t.id,
t.name,
@rownum := @rownum + 1 AS position
FROM TABLE t
JOIN (SELECT @rownum := 0) r
ORDER BY t.name)...
Vim multiline editing like in sublimetext?
...d asd asd asd;
Hit <C-v> to enter visual-block mode and expand your selection toward the bottom:
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
Hit I"<Esc> to obtain:
asd...
Better techniques for trimming leading zeros in SQL Server?
...
Why don't you just cast the value to INTEGER and then back to VARCHAR?
SELECT CAST(CAST('000000000' AS INTEGER) AS VARCHAR)
--------
0
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How to split a comma-separated value to columns
...TRING(@string, @pos, @len)
INSERT INTO @out_put ([value])
SELECT LTRIM(RTRIM(@value)) AS [column]
SET @pos = CHARINDEX(@delimiter, @string, @pos + @len) + 1
END
RETURN
END
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How do you convert a DataTable into a generic list?
...ataTable
//using lamdaexpression
emp = (from DataRow row in dt.Rows
select new Employee
{
_FirstName = row["FirstName"].ToString(),
_LastName = row["Last_Name"].ToString()
}).ToList();
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typecast string to integer - Postgres
...ur value is an empty string, you can use NULLIF to replace it for a NULL:
SELECT
NULLIF(your_value, '')::int
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