Search Results

Search found 28043 results on 1122 pages for 'sql replication'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 670/1122 | < Previous Page | 666 667 668 669 670 671 672 673 674 675 676 677  | Next Page >

  • A SELECT statement for Mysql

    - by Hossein
    I have this table: id,bookmarkID,tagID I want to fetch the top N bookmarkIDs for a given list of tags. Does anyone know a very fast solution for this? the table is quite large(12 million records) I am using MySql

    Read the article

  • 2-column table with two foreign keys. Performance/design question.

    - by Emanuel
    Hello everyone! I recently ran into a quite complex problem and after looking around a lot I couldn't find a solution to it. I've found answers to my questions many times before on stackoverflow.com, so I decided to post here. So I'm making a user/group managment system for a web-based project, and I'm storing all related data into a postgreSQL database. This system relies on three tables: USERS GROUPS GROUP_USERS The two first tables simply define all the users and all the groups on the site, and the last table, GROUP_USERS, stores the groups every user is part of. It only has two columns: USER_ID GROUP_ID Since every user can be a member of several groups, I decided to make a separate table for this purpose, rather than storing a comma separated column in the USERS-table. Now, both columns are foreign keys, and I want to make them both primary keys as well, this since each combination of USER_ID and GROUP_ID has to be unique, and if I give them the constraint UNIQUE pgAdmin tells me that each table should have at least one Primary key. But now I am stuck with what seems to be a lot of indexes and relations to a very small table only containing numbers. In the end, I want this table to be as fast as possible, even if containing tens of thousands of rows. Size on disk shouldn't be a problem since its just all numbers anyway, but it feels quite stupid to have a full-sized index refering to a smaller table. Should I stick with my current solution, store comma-separated values in a column in the USERS-table or is there any other solution I should be aware of. PS. I don't want to use an array-column, even if they are supported by postgreSQL. I want to be as generic as possible so I can switch database later on, if necessary. EDIT: I other words, will using a compound primary key and two foreign keys in one table with only two columns have a negative impact on performance rather than the opposite due to the size of the generated index? Thank you!

    Read the article

  • Alternatives to sign() in sqlite for custom order by

    - by Pentium10
    I have a string column which contains some numeric fields, but a lot are 0, empty string or null. The rest are numbers having different range, all positive. I tried to create a custom order by. The order would be done by two fields. First I would like to order the fields that have this number 0 and then sort by name. So something this would work: select * from table order by sign(referenceid) desc, name asc; But Sqlite lacks the sign() -1/0/1 function, and I am on Android and I can't create user defined functions. What other options I have to get this sort done.

    Read the article

  • MySQL Rating system (calculating average from two tables).

    - by MussuR
    I have two tables, videos and videos_ratings. The videos table has an int videoid field (and many others but those fields are not important I think) and many records. The videos_ratings table has 3 int fields: videoid, rating, rated_by which has many records (multiple records for each fields from the videos table) but not for all records from the videos table. Currently I have the following mysql query: SELECT `videos`.*, avg(`videos_ratings`.`vote`) FROM `videos`, `videos_ratings` WHERE `videos_ratings`.`videoid` = `videos`.`videoid` GROUP BY `videos_ratings`.`videoid` ORDER BY RAND() LIMIT 0, 12 It selects all the records from table videos that have a rating in table video_ratings and calculates the average correctly. But what I need is to select all records from the videos table, no matter if there is a rating for that record or not. And if there aren't any records in the videos_ratings table for that particular videos record, the average function should show 0. Hope someone could understand what I want... :) Thanks!

    Read the article

  • Count total number of callers?

    - by Kristopher Ives
    I'm currently doing this query to find the guy who makes the most calls: SELECT `commenter_name`, COUNT(*) AS `calls` FROM `comments` GROUP BY `commenter_name` ORDER BY `calls` LIMIT 1 What I want now is to be able to find out how many total unique callers. I tried using DISTINCT but I didn't get anywhere.

    Read the article

  • LINQ - if condition

    - by ile
    In code, the commented part is what I need to solve... Is there a way to write such query in LINQ? I need this because I will need sorting based on Status. var result = ( from contact in db.Contacts join user in db.Users on contact.CreatedByUserID equals user.UserID join deal in db.Deals on contact.ContactID equals deal.ContactID into deals orderby contact.ContactID descending select new ContactListView { ContactID = contact.ContactID, FirstName = contact.FirstName, LastName = contact.LastName, Email = contact.Email, Deals = deals.Count(), EstValue = deals.Sum(e => e.EstValue), SalesAgent = user.FirstName + " " + user.LastName, Tasks = 7, // This is critical part if(Deals == 0) Status = "Prospect"; else Status = "Client"; // End of critical part... }) .OrderBy(filterQuery.OrderBy + " " + filterQuery.OrderType) .Where(filterQuery.Status);

    Read the article

  • Simple aggregating query very slow in PostgreSql, any way to improve?

    - by Ash
    HI I have a table which holds files and their types such as CREATE TABLE files ( id SERIAL PRIMARY KEY, name VARCHAR(255), filetype VARCHAR(255), ... ); and another table for holding file properties such as CREATE TABLE properties ( id SERIAL PRIMARY KEY, file_id INTEGER CONSTRAINT fk_files REFERENCES files(id), size INTEGER, ... // other property fields ); The file_id field has an index. The file table has around 800k lines, and the properties table around 200k (not all files necessarily have/need a properties). I want to do aggregating queries, for example find the average size and standard deviation for all file types. But it's very slow - around 70 seconds for the latter query. I understand it needs a sequential scan, but still it seems too much. Here's the query SELECT f.filetype, avg(size), stddev(size) FROM files as f, properties as pr WHERE f.id = pr.file_id GROUP BY f.filetype; and the explain HashAggregate (cost=140292.20..140293.94 rows=116 width=13) (actual time=74013.621..74013.954 rows=110 loops=1) -> Hash Join (cost=6780.19..138945.47 rows=179564 width=13) (actual time=1520.104..73156.531 rows=179499 loops=1) Hash Cond: (f.id = pr.file_id) -> Seq Scan on files f (cost=0.00..108365.41 rows=1140941 width=9) (actual time=0.998..62569.628 rows=805270 loops=1) -> Hash (cost=3658.64..3658.64 rows=179564 width=12) (actual time=1131.053..1131.053 rows=179499 loops=1) -> Seq Scan on properties pr (cost=0.00..3658.64 rows=179564 width=12) (actual time=0.753..557.171 rows=179574 loops=1) Total runtime: 74014.520 ms Any ideas why it is so slow/how to make it faster?

    Read the article

  • Performing Inner Join for Multiple Columns in the Same Table

    - by frankiefrank
    I have a scenario which I'm a bit stuck on. Let's say I have a survey about colors, and I have one table for the color data, and another for people's answers. tbColors color_code , color_name 1 , 'blue' 2 , 'green' 3 , 'yellow' 4 , 'red' tbAnswers answer_id , favorite_color , least_favorite_color , color_im_allergic_to 1 , 1 , 2 3 2 , 3 , 1 4 3 , 1 , 1 2 4 , 2 , 3 4 For display I want to write a SELECT that presents the answers table but using the color_name column from tbColors. I understand the "most stupid" way to do it naming tbColors three times in the FROM section, using a different alias for each column to replace. How would a non-stupid way look?

    Read the article

  • writting an sql query

    - by Praveen Prasad
    iam having 2 tables table Items Table (this table holds all items iam having) itemId --------- Item1 Item2 Item3 Item4 Item5 table 2 users_item relation UserId || ItemId 1 || Item1 1 || Item2 userId one has stored 2 items Item1,Item2. Now i want to write a query on table1 (Items table) so that it displays all items which user1 has NOT chosen.

    Read the article

  • Database design advice needed.

    - by user346271
    Hi all, I'm a lone developer for a telecoms company, and am after some database design advice from anyone with a bit of time to answer. I am inserting into one table ~2 million rows each day, these tables then get archived and compressed on a monthly basis. Each monthly table contains ~15,000,000 rows. Although this is increasing month on month. For every insert I do above I am combining the data from rows which belong together and creating another "correlated" table. This table is currently not being archived, as I need to make sure I never miss an update to the correlated table. (Hope that makes sense) Although in general this information should remain fairly static after a couple of days of processing. All of the above is working perfectly. However my company now wishes to perform some stats against this data, and these tables are getting too large to provide the results in what would be deemed a reasonable time. Even with the appropriate indexes set. So I guess after all the above my question is quite simple. Should I write a script which groups the data from my correlated table into smaller tables. Or should I store the queries result sets in something like memcache? I'm already using mysqls cache, but due to having limited control over how long the data is stored for, it's not working ideally. The main advantages I can see of using something like memcache: No blocking on my correlated table after the query has been cashed. Greater flexibility of sharing the collected data between the backend collector and front end processor. (i.e custom reports could be written in the backend and the results of these stored in the cache under a key which then gets shared with anyone who would want to see the data of this report) Redundancy and scalability if we start sharing this data with a large amount of customers. The main disadvantages I can see of using something like memcache: Data is not persistent if machine is rebooted / cache is flushed. The main advantages of using MySql Persistent data. Less code changes (although adding something like memcache is trivial anyway) The main disadvantages of using MySql Have to define table templates every time I want to store provide a new set of grouped data. Have to write a program which loops through the correlated data and fills these new tables. Potentially will still grow slower as the data continues to be filled. Apologies for quite a long question. It's helped me to write down these thoughts here anyway, and any advice/help/experience with dealing with this sort of problem would be greatly appreciated. Many thanks. Alan

    Read the article

  • Best way to store a database password in a startup script / config file?

    - by Mark Harrison
    So our web server apps need to connect to the database, and some other apps have startup scripts that execute at boot time. What's the best way to store the name/password for these applications, in terms of security, e.g. perhaps we don't want sysadmins to know the database password maintainability, e.g. making the configuration easy to change when the password changes, etc. both windows and linux solutions appreciated!

    Read the article

  • Select rows where column LIKE dictionary word

    - by Gerve
    I have 2 tables: Dictionary - Contains roughly 36,000 words CREATE TABLE IF NOT EXISTS `dictionary` ( `word` varchar(255) NOT NULL, PRIMARY KEY (`word`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; Datas - Contains roughly 100,000 rows CREATE TABLE IF NOT EXISTS `datas` ( `ID` int(11) NOT NULL AUTO_INCREMENT, `hash` varchar(32) NOT NULL, `data` varchar(255) NOT NULL, `length` int(11) NOT NULL, `time` int(11) NOT NULL, PRIMARY KEY (`ID`), UNIQUE KEY `hash` (`hash`), KEY `data` (`data`), KEY `length` (`length`), KEY `time` (`time`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=105316 ; I would like to somehow select all the rows from datas where the column data contains 1 or more words. I understand this is a big ask, it would need to match all of these rows together in every combination possible, so it needs the best optimization. I have tried the below query, but it just hangs for ages: SELECT `datas`.*, `dictionary`.`word` FROM `datas`, `dictionary` WHERE `datas`.`data` LIKE CONCAT('%', `dictionary`.`word`, '%') AND LENGTH(`dictionary`.`word`) > 3 ORDER BY `length` ASC LIMIT 15 I have also tried something similar to the above with a left join, and on clause that specified the like statement.

    Read the article

  • Is a primary key automatically an index?

    - by Lieven Cardoen
    If I run Profiler, then it suggests a lot of indexes like this one CREATE CLUSTERED INDEX [_dta_index_Users_c_9_292912115__K1] ON [dbo].[Users] ( [UserId] ASC )WITH (SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF) ON [PRIMARY] UserId is the primary key of the table Users. Is this index better than the one already in the table: ALTER TABLE [dbo].[Users] ADD CONSTRAINT [PK_Users] PRIMARY KEY NONCLUSTERED ( [UserId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]

    Read the article

  • Monitoring Log Shipped Databases

    - by Registered User
    I need a consistent way to monitor databases that are read-only log shipped copies of production databases. In the past I have relied on the following methods: Set the job that restores logs to the database kick off another job as its last step. Set the job that restores logs to the database to insert a record in a control table as its last step. Query the msdb database to check the status of the job that restores logs to the database. Query a control table inside the database itself that gets a value immediately before transaction logs are backed up. Query MAX values from tables inside the database to see if it has recent changes. Although the above methods work, they can't be implemented for every log shipped database that I query for various reasons. What is the best method for monitoring the "data as of" date for a log shipped database?

    Read the article

  • Use count or have a field that tallies?

    - by Dan LaManna
    Fairly simple concept, making an extremely basic message board system and I want users to have a post count. Now I was debating on whether or not to have a tally in their row that is added each time a post by them is created, or subtracted by one each time a post of theirs is deleted. However I'm sure that performing a count query when the post count is requested would be more accurate due to unforseen circumstances (say a thread gets deleted and it doesn't lower their tally properly), however this seems like it would be less efficient to run a query EVERY time their post count is loaded, especially in the case of them having 10 posts on the same page and it lists their post count each post. Thoughts/Advice? Thanks

    Read the article

  • SimpleDB as Denormalized DB

    - by Max
    In an environment where you have a relational database which handles all business transactions is it a good idea to utilise SimpleDB for all data queries to have faster and more lightweight search? So the master data storage would be a relational DB which is "replicated"/"transformed" into SimpleDB to provide very fast read only queries since no JOINS and complicated subselects are needed.

    Read the article

  • How to use value from primary accessdatasource control as parameter in select query for secondary ac

    - by weedave
    Hi, I'm trying to display all orders placed and I have a primary accessdatasource control that has a select query to get the customer information and the orderID. I want to use the orderID value from this first query as a parameter for the secondary accessdatasource control that selects the product information of the products in the order. In plain english, I want to:- select product info from product table where orderID = ? (where ? is the orderID value from the first query) I have tried the <%#Eval("OrderID")% but I get a "server tag not well formed" error, but I do get results returned when I just type the order ID in, but obviously every result (order) just contains the same product info... <asp:Repeater ID="Repeater1" runat="server" DataSourceID="AccessDataSource1"> <ItemTemplate> <asp:AccessDataSource ID="AccessDataSource2" runat="server" DataFile="~/App_Data/project.mdb" SelectCommand="SELECT orderDetails.OrderID, album.Artist, album.Album, album.Cost, album.ImageURL, orderDetails.Quantity, orderDetails.Total FROM (album INNER JOIN orderDetails ON album.AlbumID = orderDetails.AlbumID) WHERE (orderDetails.OrderID = ? )"> <SelectParameters> // Error is on this line <asp:Parameter Name="OrderID" DefaultValue="<%#Eval ("OrderID")%>" /> </SelectParameters> </asp:AccessDataSource> <div class="viewAllOrdersOrderArea"> <div class="viewAllOrdersOrderSummary"> <p><b>Order ID: </b><%#Eval("OrderID")%></p> <h4>Shipping Details</h4> <p><b>Shipping Address: </b><%#Eval("ShippingName")%>, <%#Eval("ShippingAddress")%>, <%#Eval("ShippingTown")%>, <%#Eval("ShippingPostcode")%></p> <h4>Payment Details</h4> <p><b>Cardholder's Address: </b><%#Eval("CardHolder")%>, <%#Eval("BillingAddress")%>, <%#Eval("BillingTown")%>, <%#Eval("BillingPostcode")%></p> <p><b>Payment Method: </b><%#Eval("CardType")%></p> <p><b>Card Number: </b><%#Eval("CardNumber")%></p> <p><b>Start Date: </b><%#Eval("StartDate")%>, Expiry Date: <%#Eval("ExpiryDate")%></p> <p><b>Security Digits: </b><%#Eval("SecurityDigits")%></p> <h4>Ordered items:</h4> <asp:Repeater ID="Repeater2" runat="server" DataSourceID="AccessDataSource2"> <ItemTemplate> <div style="display: block; float: left;"> <div class="viewAllOrdersProductImage"> <img width="70px" height="70px" alt="<%# Eval("Artist") %> - <%# Eval("Album") %>" src="assets/images/thumbs/<%# Eval("ImageURL") %>" /> </div> <div style="display:block; float:left; padding-top:15px; padding-right:20px;"><p><b><%# Eval("Artist") %> - <%# Eval("Album") %></b></p> <p>£<%# Eval("Cost") %> x <%# Eval("Quantity") %> = £<%#Eval("Total")%></p></div> </div> </ItemTemplate> </asp:Repeater> </div> </div> </ItemTemplate> </asp:Repeater>

    Read the article

  • How to update a record with multiple keys

    - by OceanBlue
    I am trying a database app on Android. I want to use the SQLiteDatabase update(...) convenience method to update a record. Normally, for a WHERE clause of a single key this is working. Following code is working fine:- values.put("testname", "Quiz1"); mDB.update("Tests", values, "id=?", new String[]{"2"}); //this statement works However, I want to update a column in a table which has a combination of two keys as the unique identifier. I tried the following. This executes without exception, but nothing is updated. values.put("score", 60); mDB.update("Results", values, "studentid=? AND testid=?", new String[] { "2,1" }); // this statement does not work How to do it?

    Read the article

  • running a stored procedure inside a sql trigger

    - by Ying
    Hi all, the business logic in my application requires me to insert a row in table X when a row is inserted in table Y. Furthermore, it should only do it between specific times(which I have to query another table for). I have considered running a script every 5 minutes or so to check this, but I stumbled upon triggers and figured this might be a better way to do it. But I find the syntax for procedures a little bewildering and I keep getting an error I have no idea how to fix. Here is where I start: CREATE TRIGGER reservation_auto_reply AFTER INSERT ON reservation FOR EACH ROW BEGIN IF NEW.sent_type = 1 /* In-App */ THEN INSERT INTO `messagehistory` (`trip`, `fk`, `sent_time`, `status`, `message_type`, `message`) VALUES (NEW.trip, NEW.psk, 'NOW()', 'submitted', 4, 'This is an automated reply to reservation'); END; I get an error in the VALUES part of the statmenet but im not sure where. I still have to query the other table for the information I need, but I can't even get past this part. Any help is appreciated, including links to many examples..Thanks

    Read the article

  • How to join two query in SQL (Oracle)

    - by MAHESH A SONI
    How can I join these queries? SELECT RCTDT, SUM(RCTAMOUNT), COUNT(RCTAMOUNT) FROM RECEIPTS4 WHERE RCTDT BETWEEN '01-nov-2009' AND '30-nov-2009' AND RCTTYPE='CA' AND RCTAMOUNT>0 GROUP BY RCTDT --- SELECT RCTDT, SUM(RCTAMOUNT), COUNT(RCTAMOUNT) FROM RECEIPTS4 WHERE RCTDT BETWEEN '01-nov-2009' AND '30-nov-2009' AND RCTTYPE='CQ' AND RCTAMOUNT>0 GROUP BY RCTDT

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 666 667 668 669 670 671 672 673 674 675 676 677  | Next Page >