大约有 44,000 项符合查询结果（耗时：0.0392秒） [XML]
How to merge a list of lists with same type of items to a single list of items?
...es, convert each TSource in the list into an IEnumerable of TResults, then concatenate all those IEnumerables into one big one. In this case you have a list of lists to start, so if you want to concatenate them the function to map from a TSource (which is an IEnumerable of TResults) to an IEnumerabl...
How do I add more members to my ENUM-type column in MySQL?
... and column_name=@column_name;
set @tmp = insert(@tmp, instr(@tmp,')'), 0, concat(',\'', @new_enum, '\'') );
set @tmp = concat('alter table ', @table_name, ' modify ', @column_name, ' ', @tmp);
prepare stmt from @tmp;
execute stmt;
deallocate prepare stmt;
...
UPDATE multiple tables in MySQL using LEFT JOIN
...eld text in table A with
UPDATE `Table A`,`Table B`
SET `Table A`.`text`=concat_ws('',`Table A`.`text`,`Table B`.`B-num`," from
",`Table B`.`date`,'/')
WHERE `Table A`.`A-num` = `Table B`.`A-num`
and come to this result:
Table A
+--------+------------...
Adding a directory to $LOAD_PATH (Ruby)
...nt.rb file:
Rails::Initializer.run do |config|
* * * * *
path = []
path.concat($LOAD_PATH)
$LOAD_PATH.clear
$LOAD_PATH << 'C:\web\common\lib'
$LOAD_PATH << 'C:\web\common'
$LOAD_PATH.concat(path)
* * * * *
end
I don't think you can use any of the advanced coding constructs given b...
What does axis in pandas mean?
...0 means along "indexes". It's a row-wise operation.
Suppose, to perform concat() operation on dataframe1 & dataframe2,
we will take dataframe1 & take out 1st row from dataframe1 and place into the new DF, then we take out another row from dataframe1 and put into new DF, we repeat this pro...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...or operation '='
$this->db->select("users.username as matric_no, CONCAT(users.surname,
' ',
users.first_name, ' ', users.last_name) as fullname")
->join('users', 'users.username=classroom_students.matric_no', 'left')
->where('classroom_students.sessio...
How to change the foreign key referential action? (behavior)
...wrote something to make the statements for me. Figured I'd share:
SELECT
CONCAT('ALTER TABLE `' ,rc.TABLE_NAME,
'` DROP FOREIGN KEY `' ,rc.CONSTRAINT_NAME,'`;')
, CONCAT('ALTER TABLE `' ,rc.TABLE_NAME,
'` ADD CONSTRAINT `' ,rc.CONSTRAINT_NAME ,'` FOREIGN KEY (`',kcu.COLUMN_NAME,
'`) RE...
Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
...apply different aggregation functions to different columns, one could also concat the resulting data frames using pd.concat. This maybe easier to read than subsqeuent chaining
– Quickbeam2k1
Aug 17 '16 at 11:26
...
How to move columns in a MySQL table?
...oringColumn = '<YOUR COLUMN SHOULD COME AFTER THIS COLUMN>';
SELECT CONCAT("ALTER TABLE `",t.TABLE_NAME,"` CHANGE COLUMN `",COLUMN_NAME,"`
`",COLUMN_NAME,"` ", c.DATA_TYPE, CASE WHEN c.CHARACTER_MAXIMUM_LENGTH IS NOT
NULL THEN CONCAT("(", c.CHARACTER_MAXIMUM_LENGTH, ")") ELSE "" END ," AFT...
A proper wrapper for console.log with correct line number?
...eNumberFromStack(this.stack)
)
};
args = args.concat([suffix]);
// via @paulirish console wrapper
if (console && console.log) {
if (console.log.apply) { console.log.apply(console, args); } else { console.log(args); } // nicer display i...