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Include headers when using SELECT INTO OUTFILE?
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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
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Selecting a row in DataGridView programmatically
How can I select a particular range of rows in a DataGridView programmatically at runtime?
8 Answers
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How to use clock() in C++
...0;
int min = 0;
int hr = 0;
//cout << "Press any key to start:";
//char start = _gtech();
for (;;)
{
newline();
if(msec == 1000)
{
++sec;
msec = 0;
}
if(sec == 60)
...
Max length for client ip address [duplicate]
...x digits separated by colons: 2001:0db8:85a3:0000:0000:8a2e:0370:7334. 39 characters is appropriate to store IPv6 addresses in this format.
Edit: However, there is a caveat, see @Deepak's answer for details about IPv4-mapped IPv6 addresses. (The correct maximum IPv6 string length is 45 characters....
Get top n records for each group of grouped results
...ould need to specify the group number and add queries for each group:
(
select *
from mytable
where `group` = 1
order by age desc
LIMIT 2
)
UNION ALL
(
select *
from mytable
where `group` = 2
order by age desc
LIMIT 2
)
There are a variety of ways to do this, see this articl...
Any way to select without causing locking in MySQL?
...s/22-mysql-with-nolock.aspx
in MS SQL Server you would do the following:
SELECT * FROM TABLE_NAME WITH (nolock)
and the MYSQL equivalent is
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED ;
SELECT * FROM TABLE_NAME ;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ ;
EDIT
Mic...
When to use Common Table Expression (CTE)
...ing well? Can someone give me a simple example of limitations with regular select, derived or temp table queries to make the case of CTE? Any simple examples would be highly appreciated.
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How to request a random row in SQL?
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See this post: SQL to Select a random row from a database table. It goes through methods for doing this in MySQL, PostgreSQL, Microsoft SQL Server, IBM DB2 and Oracle (the following is copied from that link):
Select a random row with MySQL:
SELE...
How to drop all tables in a SQL Server database?
...VARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS t...
Is there a goto statement in Java?
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@mwieczorek Not all. "char" is a primitive type and it's unsigned.
– Sergey Krivenkov
Nov 20 '18 at 9:47
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