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What is the fastest substring search algorithm?
...e one that performs best with your data.
Boyer-Moore uses a bad character table with a good suffix table.
Boyer-Moore-Horspool uses a bad character table.
Knuth-Morris-Pratt uses a partial match table.
Rabin-Karp uses running hashes.
They all trade overhead for reduced comparisons to a differen...
Large, persistent DataFrame in pandas
...le paths
in_csv = '../data/my_large.csv'
out_sqlite = '../data/my.sqlite'
table_name = 'my_table' # name for the SQLite database table
chunksize = 100000 # number of lines to process at each iteration
# columns that should be read from the CSV file
columns = ['molecule_id','charge','db','drugsnow'...
Downloading MySQL dump from command line
...mp -u [uname] -p --all-databases > all_db_backup.sql
If it's specific tables within a DB, then:
$ mysqldump -u [uname] -p db_name table1 table2 > table_backup.sql
You can even go as far as auto-compressing the output using gzip (if your DB is very big):
$ mysqldump -u [uname] -p db...
Add default value of datetime field in SQL Server to a timestamp
I've got a table that collects forms submitted from our website, but for some reason, when they created the table, they didn't put a timestamp in the table. I want it to enter the exact date and time that the record was entered.
...
What is hashCode used for? Is it unique?
...n index for an object
in a collection.
The GetHashCode method is suitable for use in hashing algorithms and
data structures such as a hash table.
The default implementation of the GetHashCode method does not
guarantee unique return values for different objects. Furthermore, the
.NE...
WHERE vs HAVING
... answers on this question didn't hit upon the key point.
Assume we have a table:
CREATE TABLE `table` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`value` int(10) unsigned NOT NULL,
PRIMARY KEY (`id`),
KEY `value` (`value`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
And have 10 rows with both ...
Update all values of a column to lowercase
...v.mysql.com/doc/refman/5.0/en/string-functions.html#function_lower
UPDATE table_name SET tag = LOWER(tag)
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Primary key/foreign Key naming convention [closed]
...un, have them specify at length why their method is superior for recursive table references.
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Foreign key constraint may cause cycles or multiple cascade paths?
I have a problem when I try to add constraints to my tables. I get the error:
9 Answers
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Angular.js ng-repeat across multiple tr's
...test through an html validator allowed multiple tbody elements in the same table.
Update: As of at least Angular 1.2 there is an ng-repeat-start and ng-repeat-end to allow repeating a series of elements. See the documentation for more information and thanks to @Onite for the comment!
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