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What is the size of column of int(11) in mysql in bytes?
...prefixed with 0s.
The best way to see all the nuances is to run:
CREATE TABLE `mytable` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`int1` int(10) NOT NULL,
`int2` int(3) NOT NULL,
`zf1` int(10) ZEROFILL NOT NULL,
`zf2` int(3) ZEROFILL NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=Inn...
Removing index column in pandas when reading a csv
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Using df.to_sql("table",cursor,if_exists="append",index=False) also fixes the sqlite error sqlite3.OperationalError: table message has no column named index
– Anna
Jun 3 '18 at 0:55
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Explain the use of a bit vector for determining if all characters are unique
...of both operands to left and right of it.
So what we have here is a hash table which is being stored in a 32 bit binary number every time the checker gets or'd ( checker |= (1 << val)) with the designated binary value of a letter its corresponding bit it is being set to true.
The character's...
Difference between float and decimal data type
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This is what I found when I had this doubt.
mysql> create table numbers (a decimal(10,2), b float);
mysql> insert into numbers values (100, 100);
mysql> select @a := (a/3), @b := (b/3), @a * 3, @b * 3 from numbers \G
*************************** 1. row *************************...
how to add records to has_many :through association in rails
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'The best way' depends on your needs and what feels most comfortable. Confusion comes from differences ActiveRecord's behavior of the new and create methods and the << operator.
The new Method
new will not add an association record for you. You have to build the House and Agent ...
What is the optimal Jewish toenail cutting algorithm?
... the fewer toes case is covered by the original algorithm (acceptable sequences for 5 toes are acceptable for 4 toes). It's those crazy extra toes that cause problems ;)
– flies
Oct 14 '11 at 14:47
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How to concatenate strings of a string field in a PostgreSQL 'group by' query?
...e the strings of a field within a group by query. So for example, I have a table:
14 Answers
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When is the init() function run?
...s this way.
A lot of the internal Go packages use init() to initialize tables and such, for example https://github.com/golang/go/blob/883bc6/src/compress/bzip2/bzip2.go#L480
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PostgreSQL: Is it better to use multiple databases with one schema each, or one database with multip
...LongTermStorage" and so on. "UserManagement" would then contain the "User" table, as well as all stored procedures, triggers, sequences, etc. that are needed for the user management.
Databases are entire programs, schemas are components.
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Increment a database field by 1
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Updating an entry:
A simple increment should do the trick.
UPDATE mytable
SET logins = logins + 1
WHERE id = 12
Insert new row, or Update if already present:
If you would like to update a previously existing row, or insert it if it doesn't already exist, you can use the REPLACE synta...