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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;
...
static const vs #define
...l than a post-preprocessing "if" as the code need not be compilable if not selected by the preprocessor), use #undef-ine, redefine etc.
substituted text has to be exposed:
in the translation unit it's used by, which means macros in libraries for client use must be in the header, so make and other ...
How to read a CSV file into a .NET Datatable
...e(path);
string fileName = Path.GetFileName(path);
string sql = @"SELECT * FROM [" + fileName + "]";
using(OleDbConnection connection = new OleDbConnection(
@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathOnly +
";Extended Properties=\"Text;HDR=" + h...
How do I trim leading/trailing whitespace in a standard way?
... allocated. The return
// value must NOT be deallocated using free() etc.
char *trimwhitespace(char *str)
{
char *end;
// Trim leading space
while(isspace((unsigned char)*str)) str++;
if(*str == 0) // All spaces?
return str;
// Trim trailing space
end = str + strlen(str) - 1;
...
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...
Import CSV file to strongly typed data structure in .Net [closed]
...tring);
objConn.Open();
DataTable dt = new DataTable();
OleDbCommand objCmdSelect = new OleDbCommand("SELECT * FROM file.csv", objConn);
OleDbDataAdapter objAdapter1 = new OleDbDataAdapter();
objAdapter1.SelectCommand = objCmdSelect;
objAdapter1.Fill(dt);
objConn.Close();
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How to make MySQL handle UTF-8 properly
...til just recently), and not complete (does not discuss correctly inserting/selecting utf8-encoded data, nor displaying in html).
– Rick James
Jan 20 '16 at 3:28
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Can I embed a custom font in an iPhone application?
...Full name" of the font, which is visible by opening it up in Font Book and selecting: Preview --> Show Font Info
– electromaggot
Nov 20 '11 at 8:16
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Delete column from SQLite table
... TRANSACTION;
CREATE TEMPORARY TABLE t1_backup(a,b);
INSERT INTO t1_backup SELECT a,b FROM t1;
DROP TABLE t1;
CREATE TABLE t1(a,b);
INSERT INTO t1 SELECT a,b FROM t1_backup;
DROP TABLE t1_backup;
COMMIT;
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Difference between signed / unsigned char [duplicate]
...gnify if the number if positive or negative, but how does this apply to a char ? How can a character be positive or negative?
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