I have a query which selects 6 names in the database. eg
SELECT names FROM users LIMIT 6
Now I want this query to select a random 6 names in the database table, is this possible? And how
I seem to have two options on how to implement arrays, and I want to know which I should go with:
Use the ARRAY data type and (from what I understand) effectively serialize data objects into the database (which in my case are just wrapped primitive types; don't know of another way to make this work).
Use a separate table and map with foreign keys for each array item.
If you have experience with this (especially with H2), which would you recommend?
I have this table...
--------------------------------------
| user_id | status | status_date |
--------------------------------------
| 1 | Current | 2012-08-01 |
| 1 | Referral | 2012-03-14 |
| 2 | Referral | 2012-04-23 |
| | | |
--------------------------------------
How would I query to find a distinct user_id who has a referral date before 2012-06-30 AND either a current date of after 2012-06-30 or no current status record at all?
Database is MySQL.
Hi all, would the following Jquery selector get all of the 4th td elements of all the tables on the current page, and return their text as an array?:
var isbn = $.makeArray($("table tr td:nth-child(4)").text());
I wonder if this is possible with straight SQL on MySQL. I need to do SELECT COUNT(*) FROM on each table in the database and output results in one result set.
Is it possible to do with just SQL?
I have these rows in a table
ID Name Price Delivery
== ==== ===== ========
1 apple 1 1
2 apple 3 2
3 apple 6 3
4 apple 9 4
5 orange 4 6
6 orange 5 7
I want to have the price at the third delivery (Delivery=3) or the last price if there's no third delivery.
It would give me this :
ID Name Price Delivery
== ==== ===== ========
3 apple 6 3
6 orange 5 7
I don't necessary want a full solution but an idea of what to look for would be greatly appreciated.
All,
I have a database table in mysql with a field that is of "TIMESTAMP" type. I need help writing the SQL query to update the field with the current timestamp.
UPDATE tb_Test set dt_modified = ?????
Thanks,
Is there a CSS library which mimics the iPhone grouped UITableView?
I want to build a nice looking table which looks exactly like the grouped UITableView. As there are multiple text styles within the each line of text, and I don't need any interactivity except scrolling, it seems it would be easier to build with HTML and display it in a UIWebView. Is there a css library which matches this need?
The mysql table has a DATETIME field. I want to INSERT a new row into this field using the cell data from the Excel worksheet. But I cannot use the datetime formatted cell value in a INSERT INTO query. How can I implement this?
Hello,
I 've got a table field (membername) which contains both the last name and the first name of users. Is it possible to split those into 2 fields (memberfirst - memberlast)? All the records have this format "Firstname Lastname" (without quotes and a space in between).
We're montioring usage of a certain resources by monitoring users logins (We can see user logins growing daily). After filtering out repeat inter day logins for users, we'd like to track the # of users using the service each day, and then using that info to determine overall incremental gains for each calendar day. Our table is pretty simple:
class ServiceLogin
{
String login;
DateTime loginTime;
}
Hi,
I have a table that looks like this:
----------------------
| DateTime | Value |
----------------------
| 2010-01-01 | 26 |
| 2010-02-01 | 24 |
| 2010-03-01 | 23 |
| 2010-04-01 | 28 |
| 2010-05-01 | 30 |
I need to find if the last three consecutive months have increased in value.
How can I get SQL to check whether the value for each has increased?
If anyone can give me any pointers for solving this problem it would be greatly appreciated!
Thanks
We have a database setup that consists of two parts: a static structure, and dynamic additions. For each database, the dynamic can be different, and sometimes we don't have data for all the dynamic fields. Rigt now, we check for empties by looking at the total count of records in the entire table, but we want to move to a more refined method of checking for empties if possible. Is it possible to quickly check through several hundred fields and see which ones are empty and which ones are populated?
I have data from a database loaded into a JTable through a custom table model. I want to have a column (should be the first column) which simply shows the display row number (i.e. it is not tied to any data (or sorting) but is simply the row number on the screen starting at 1). These "column headers" should be grayed out like the row headers.
Any idea how to do this?
Thanks
I'm trying to make a graph of a table and graph it in log space.
First of all, plot(dat) gives me the grid of graphs
Second of all, plot(dat, log="xy") gives me the correct plots of data in log space
However, plot(dat, log="xy") ruins the main diagonal's labels of names(dat)
R version 2.11.0
I have a java class containing all the columns of a database table as attributes (member variables) and corresponding getters and setters.
I want to have a method in this class called getColumnCount() that returns the number of columns (i.e. the number of attributes in the class)? How would I implement this without hardcoding the number? I am open to critisims on this in general and suggestions. Thanks.
sorry for the (probably) noob question, but I', new at this stuff.
i have a table that has column 'position', and I want to, when inserting a new row, change positions of every row that has position lower than row that is inserted. for example, if I add row with position 4, if there is a duplicate, it should become 5, 5 should shift to 6 and so on...
also, is there a way to get highest value for column besides testing it in every row via php?
Here's my table with some sample data
a_id | b_id
------------
1 225
2 494
3 589
When I run this query
INSERT IGNORE INTO table_name (a_id, b_id) VALUES ('4', '230') ('2', '494')
It inserts both those rows when it's supposed to ignore the second value pair (2, 494)
No indexes defined, neither of those columns are primary.
What don't I know?
table is bbc(name, region, area, population, gdp)
Some countries have populations more than three times that of any of their neighbours (in the same region). Give the countries and regions.
Please help.
I have a table with 42 million records. 32 million have a null value and I would like to generate a new guid for each one. Should I do this in batches?
Also, going forward, I would like a new guid added to the field on the insert of a new record. What is the best way to do this?
The field is not the primary key, which is an auto-incrementing integer.
SSIS performance degrades when using bulk insert task in for each loop to upload multiple files into one target table. how to maintain SSIS performance
Suppose you have a string: "SELECT * FROM TABLE WHERE column1 = :var1 AND column2 = :var2"
Now, how do I get an array with all the variables like so:
Array
(
[0] => :var1
[1] => :var2
)
I've tried it with PHP's preg_match_all, but I struggle with the regex.
$varcount = preg_match_all("/ :.+ /", $sql, $out);
I'm executing the following query
SELECT COUNT(*)
FROM table
WHERE field1='value' AND (field2 = 1000 OR field3 = 2000)
There is one index over field1 and another composited over field2&field3.
I see MySQL always selects the field1 index and then makes a join using the other two fields which is quite bad because it needs to join 146.000 rows.
Suggestions on how to improve this? Thanks
What is the easiest and most efficient way to create an auto-increment counter for every data row in google appengine?
basically I want to give every row a unique row_number so that I can overcome the issue of only being able to get the first 1000 results in a select query. I can thus add a counter lies between condition and mine all the entires in the table.
In my Django app, I just ran
$ python manage.py sqlall
and I see a lot of SQL statements that look like this, when describing FK relationships:
ALTER TABLE `app1_model1` ADD CONSTRAINT model2_id_refs_id_728de91f FOREIGN KEY (`model2_id`) REFERENCES `app1_model2` (`id`);
Where does "7218de91f" come from? I would like to know because I'd like to manually write SQL statements to accompany models changes in the app so that my db's can be kept up to date.