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Get record counts for all tables in MySQL database
Is there a way to get the count of rows in all tables in a MySQL database without running a SELECT count() on each table?
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What integer hash function are good that accepts an integer hash key?
...hich is not uncommon), their hashes will be too. This is a problem in hash tables - you can end up with only 1/2 or 1/4 of the buckets being used.
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PostgreSQL create table if not exists
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This feature has been implemented in Postgres 9.1:
CREATE TABLE IF NOT EXISTS myschema.mytable (i integer);
For older versions, here is a function to work around it:
CREATE OR REPLACE FUNCTION create_mytable()
RETURNS void
LANGUAGE plpgsql AS
$func$
BEGIN
IF EXISTS (SELECT...
PHP code to convert a MySQL query to CSV [closed]
...MINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY "\n"
FROM my_table;
(the documentation for this is here: http://dev.mysql.com/doc/refman/5.0/en/select.html)
or:
$select = "SELECT * FROM table_name";
$export = mysql_query ( $select ) or die ( "Sql error : " . mysql_error( ) );
$fi...
How to implement a rule engine?
I have a db table that stores the following:
10 Answers
10
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Error in finding last used cell in Excel with VBA
...ow
Else
lastrow = 1
End If
End With
Find Last Row in a Table (ListObject)
The same principles apply, for example to get the last row in the third column of a table:
Sub FindLastRowInExcelTableColAandB()
Dim lastRow As Long
Dim ws As Worksheet, tbl as ListObject
Set ws = Sheets(...
How to use ng-repeat without an html element
... on tbody? (AFAIK, it is okay to have multiple <tbody>s in a single table.)
<tbody ng-repeat="row in array">
<tr ng-repeat="item in row">
<td>{{item}}</td>
</tr>
</tbody>
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List all tables in postgresql information_schema
What is the best way to list all of the tables within PostgreSQL's information_schema?
8 Answers
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Which SQL query is faster? Filter on Join criteria or Where clause?
...LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = a.ID
AND a.ID = 1
LEFT JOIN
TableB b
ON x.TableBID = b.ID
or this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAI...
@UniqueConstraint annotation in Java
...@UniqueConstraint annotation is for annotating multiple unique keys at the table level, which is why you get an error when applying it to a field.
References (JPA TopLink):
@UniqueConstraint
@Column
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