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How to remove leading and trailing whitespace in a MySQL field?
...d the use case before using this solution:
trim does not work while doing select query
This works
select replace(name , ' ','') from test;
While this doesn't
select trim(name) from test;
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...
Cast int to varchar
...datatype, there is no varchar datatype that you can cast/convert data to:
select CAST(id as CHAR(50)) as col1
from t9;
select CONVERT(id, CHAR(50)) as colI1
from t9;
See the following SQL — in action — over at SQL Fiddle:
/*! Build Schema */
create table t9 (id INT, name VARCHAR(55));
ins...
byte[] to hex string [duplicate]
...);
}
static string LinqConcat(byte[] data)
{
return string.Concat(data.Select(b => b.ToString("X2")).ToArray());
}
static string LinqJoin(byte[] data)
{
return string.Join("",
data.Select(
bin => bin.ToString("X2")
).ToArray());
}
static string LinqAgg(b...
IEnumerable to string [duplicate]
...urer sequence, rather than a cast. Something like Enumerable.Range(65, 26).Select(i => (char)i);, this should avoid the chance for an optimized shortcut.
– Jodrell
Oct 28 '13 at 9:39
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Can I concatenate multiple MySQL rows into one field?
...
You can use GROUP_CONCAT:
SELECT person_id, GROUP_CONCAT(hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Ludwig stated in his comment, you can add the DISTINCT operator to avoid duplicates:
SELECT person_id, GROUP_CONCAT(DISTINCT ...
Capitalize first letter. MySQL
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You can use a combination of UCASE(), MID() and CONCAT():
SELECT CONCAT(UCASE(MID(name,1,1)),MID(name,2)) AS name FROM names;
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Pad a string with leading zeros so it's 3 characters long in SQL Server 2008
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If the field is already a string, this will work
SELECT RIGHT('000'+ISNULL(field,''),3)
If you want nulls to show as '000'
It might be an integer -- then you would want
SELECT RIGHT('000'+CAST(field AS VARCHAR(3)),3)
As required by the question this answer only w...
How to concatenate columns in a Postgres SELECT?
... an explicit coercion to text [...]
Bold emphasis mine. The 2nd example (select a||', '||b from foo) works for any data types since the untyped string literal ', ' defaults to type text making the whole expression valid in any case.
For non-string data types, you can "fix" the 1st statement by c...
How to use GROUP_CONCAT in a CONCAT in MySQL
...
select id, group_concat(`Name` separator ',') as `ColumnName`
from
(
select
id,
concat(`Name`, ':', group_concat(`Value` separator ',')) as `Name`
from mytbl
group by
id,
`Name`
) tbl
group by id;
...
How to use GROUP BY to concatenate strings in MySQL?
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SELECT id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
From the link above, GROUP_CONCAT: This function returns a string res...