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For loop example in MySQL
...
drop table if exists foo;
create table foo
(
id int unsigned not null auto_increment primary key,
val smallint unsigned not null default 0
)
engine=innodb;
drop procedure if exists load_foo_test_data;
delimiter #
create procedur...
Using CSS td width absolute, position
...
This may not be what you want to hear, but display: table-cell does not respect width and will be collapsed based on the width of the entire table. You can get around this easily just by having a display: block element inside of the table cell itself whose width you specify, ...
How do HashTables deal with collisions?
I've heard in my degree classes that a HashTable will place a new entry into the 'next available' bucket if the new Key entry collides with another.
...
Difference between Key, Primary Key, Unique Key and Index in MySQL
...on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called users and you want to search for all the users which have the last name 'Smith'. Without an index, the database would have to go through all the records of the table: this is slow, because the more records you ha...
Can a foreign key be NULL and/or duplicate?
...mply requires that the value in that field must exist first in a different table (the parent table). That is all an FK is by definition. Null by definition is not a value. Null means that we do not yet know what the value is.
Let me give you a real life example. Suppose you have a database that sto...
How to join (merge) data frames (inner, outer, left, right)
...f performance is a major issue for you, you should also look into the data.table package - that's a whole new set of join syntax, but it's radically faster than anything we're talking about here.
– Matt Parker
Feb 12 '13 at 16:22
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Android Studio: how to attach Android SDK sources?
...for SDK is available only for API levels 14 and above.
UPDATE ( Based on stable release 3.2.1):
Google changes the approach of shipping the sources, so lets see what changed.
Go to the following location
Preferences -> Apperance & Behaviour -> System Settings -> Android SDK
Quite ...
Is the LIKE operator case-sensitive with MSSQL Server?
...al_cp1_cs_as
(d) To create a column using a different collation
create table exampletable (
examplecolumn varchar(10) collate sql_latin1_general_cp1_ci_as null
)
(e) To modify a column collation
alter table exampletable
alter column examplecolumn varchar(10) collate sql_latin1_general_cp1...
Count table rows
What is the MySQL command to retrieve the count of records in a table?
11 Answers
11
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How to get all columns' names for all the tables in MySQL?
Is there a fast way of getting all column names from all tables in MySQL , without having to list all the tables?
10 Answe...