Search Results

Search found 4788 results on 192 pages for 'adhoc queries'.

Page 67/192 | < Previous Page | 63 64 65 66 67 68 69 70 71 72 73 74  | Next Page >

  • autocommit and @Transactional and Cascading with spring, jpa and hibernate

    - by subes
    Hi, what I would like to accomplish is the following: have autocommit enabled so per default all queries get commited if there is a @Transactional on a method, it overrides the autocommit and encloses all queries into a single transaction, thus overriding the autocommit if there is a @Transactional method that calls other @Transactional annotated methods, the outer most annotation should override the inner annotaions and create a larger transaction, thus annotations also override eachother I am currently still learning about spring-orm and couldn't find documentation about this and don't have a test project for this yet. So my questions are: What is the default behaviour of transactions in spring? If the default differs from my requirement, is there a way to configure my desired behaviour? Or is there a totally different best practice for transactions? --EDIT-- I have the following test-setup: @javax.persistence.Entity public class Entity { @Id @GeneratedValue private Integer id; private String name; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } } @Repository public class Dao { @PersistenceContext private EntityManager em; public void insert(Entity ent) { em.persist(ent); } @SuppressWarnings("unchecked") public List<Entity> selectAll() { List<Entity> ents = em.createQuery("select e from " + Entity.class.getName() + " e").getResultList(); return ents; } } If I have it like this, even with autocommit enabled in hibernate, the insert method does nothing. I have to add @Transactional to the insert or the method calling insert for it to work... Is there a way to make @Transactional completely optional?

    Read the article

  • Optimizing MySQL update query

    - by Jernej Jerin
    This is currently my MySQL UPDATE query, which is called from program written in Java: String query = "UPDATE maxday SET DatePressureREL = (SELECT Date FROM ws3600 WHERE PressureREL = (SELECT MAX" + "(PressureREL) FROM ws3600 WHERE Date >= '" + Date + "') AND Date >= '" + Date + "' ORDER BY Date DESC LIMIT 1), " + "PressureREL = (SELECT PressureREL FROM ws3600 WHERE PressureREL = (SELECT MAX(PressureREL) FROM ws3600 " + "WHERE Date >= '" + Date + "') AND Date >= '" + Date + "' ORDER BY Date DESC LIMIT 1), ..."; try { s.execute(query); } catch (SQLException e) { System.out.println("SQL error"); } catch(Exception e) { e.printStackTrace(); } Let me explain first, what does it do. I have two tables, first is ws3600, which holds columns (Date, PressureREL, TemperatureOUT, Dewpoint, ...). Then I have second table, called maxday, which holds columns like DatePressureREL, PressureREL, DateTemperatureOUT, TemperatureOUT,... Now as you can see from an example, I update each column, the question is, is there a faster way? I am asking this, because I am calling MAX twice, first to find the Date for that value and secondly to find the actual value. Now I know that I could write like that: SELECT Date, PressureREL FROM ws3600 WHERE PressureREL = (SELECT MAX(PressureREL) FROM ws3600 WHERE Date >= '" + Date + "') AND Date >= '" + Date + "' ORDER BY Date DESC LIMIT 1 That way I get the Date of the max and the max value at the same time and then update with those values the data in maxday table. But the problem of this solution is, that I have to execute many queries, which as I understand takes alot more time compared to executing one long mysql query because of overhead in sending each query to the server. If there is no better way, which solution beetwen this two should I choose. The first, which only takes one query but is very unoptimized or the second which is beter in terms of optimization, but needs alot more queries which probably means that the preformance gain is lost because of overhead in sending each query to the server?

    Read the article

  • Does query plan optimizer works well with joined/filtered table-valued functions?

    - by smoothdeveloper
    In SQLSERVER 2005, I'm using table-valued function as a convenient way to perform arbitrary aggregation on subset data from large table (passing date range or such parameters). I'm using theses inside larger queries as joined computations and I'm wondering if the query plan optimizer work well with them in every condition or if I'm better to unnest such computation in my larger queries. Does query plan optimizer unnest table-valued functions if it make sense? If it doesn't, what do you recommend to avoid code duplication that would occur by manually unnesting them? If it does, how do you identify that from the execution plan? code sample: create table dbo.customers ( [key] uniqueidentifier , constraint pk_dbo_customers primary key ([key]) ) go /* assume large amount of data */ create table dbo.point_of_sales ( [key] uniqueidentifier , customer_key uniqueidentifier , constraint pk_dbo_point_of_sales primary key ([key]) ) go create table dbo.product_ranges ( [key] uniqueidentifier , constraint pk_dbo_product_ranges primary key ([key]) ) go create table dbo.products ( [key] uniqueidentifier , product_range_key uniqueidentifier , release_date datetime , constraint pk_dbo_products primary key ([key]) , constraint fk_dbo_products_product_range_key foreign key (product_range_key) references dbo.product_ranges ([key]) ) go . /* assume large amount of data */ create table dbo.sales_history ( [key] uniqueidentifier , product_key uniqueidentifier , point_of_sale_key uniqueidentifier , accounting_date datetime , amount money , quantity int , constraint pk_dbo_sales_history primary key ([key]) , constraint fk_dbo_sales_history_product_key foreign key (product_key) references dbo.products ([key]) , constraint fk_dbo_sales_history_point_of_sale_key foreign key (point_of_sale_key) references dbo.point_of_sales ([key]) ) go create function dbo.f_sales_history_..snip.._date_range ( @accountingdatelowerbound datetime, @accountingdateupperbound datetime ) returns table as return ( select pos.customer_key , sh.product_key , sum(sh.amount) amount , sum(sh.quantity) quantity from dbo.point_of_sales pos inner join dbo.sales_history sh on sh.point_of_sale_key = pos.[key] where sh.accounting_date between @accountingdatelowerbound and @accountingdateupperbound group by pos.customer_key , sh.product_key ) go -- TODO: insert some data -- this is a table containing a selection of product ranges declare @selectedproductranges table([key] uniqueidentifier) -- this is a table containing a selection of customers declare @selectedcustomers table([key] uniqueidentifier) declare @low datetime , @up datetime -- TODO: set top query parameters . select saleshistory.customer_key , saleshistory.product_key , saleshistory.amount , saleshistory.quantity from dbo.products p inner join @selectedproductranges productrangeselection on p.product_range_key = productrangeselection.[key] inner join @selectedcustomers customerselection on 1 = 1 inner join dbo.f_sales_history_..snip.._date_range(@low, @up) saleshistory on saleshistory.product_key = p.[key] and saleshistory.customer_key = customerselection.[key] I hope the sample makes sense. Much thanks for your help!

    Read the article

  • SQL Server Index cost

    - by yellowstar
    I have read that one of the tradeoffs for adding table indexes in SQL Server is the increased cost of insert/update/delete queries to benefit the performance of select queries. I can conceptually understand what happens in the case of an insert because SQL Server has to write entries into each index matching the new rows, but update and delete are a little more murky to me because I can't quite wrap my head around what the database engine has to do. Let's take DELETE as an example and assume I have the following schema (pardon the pseudo-SQL) TABLE Foo col1 int ,col2 int ,col3 int ,col4 int PRIMARY KEY (col1,col2) INDEX IX_1 col3 INCLUDE col4 Now, if I issue the statement DELETE FROM Foo WHERE col1=12 AND col2 > 34 I understand what the engine must do to update the table (or clustered index if you prefer). The index is set up to make it easy to find the range of rows to be removed and do so. However, at this point it also needs to update IX_1 and the query that I gave it gives no obvious efficient way for the database engine to find the rows to update. Is it forced to do a full index scan at this point? Does the engine read the rows from the clustered index first and generate a smarter internal delete against the index? It might help me to wrap my head around this if I understood better what is going on under the hood, but I guess my real question is this. I have a database that is spending a significant amount of time in delete and I'm trying to figure out what I can do about it. When I display the execution plan for the deletion, it just shows an entry for "Clustered Index Delete" on table Foo which lists in the details section the other indices that need to be updated but I don't get any indication of the relative cost of these other indices. Are they all equal in this case? Is there some way that I can estimate the impact of removing one or more of these indices without having to actually try it?

    Read the article

  • PDO empy result from SELECT when using AND

    - by Jurgen
    Hello, I've come upon a rather interesting thing, which I can't seem to figure out myself. Everytime when executing a SQL statement which contains a '... AND ...' the result is empty. Example: echo('I have a user: ' . $email . $wachtwoord . '<br>'); $dbh = new PDO($dsn, $user, $password); $sql = 'SELECT * FROM user WHERE email = :email AND wachtwoord= :wachtwoord'; $stmt = $dbh->prepare($sql); $stmt->bindParam(:email,$email,PDO::PARAM_STR); $stmt->bindParam(:wachtwoord,$wachtwoord,PDO::PARAM_STR); $stmt->execute(); while($row = $stmt->fetchObject()) { echo($row-email . ',' . $row-wachtwoord); $user[] = array( 'email' = $row-email, 'wachtwoord' = $row-wachtwoord ); } The first echo displays the correct values, however the line with echo($row->email . ',' . $row->wachtwoord); is never reached. A few things I want to add: 1) I am connected to the database since other queries work, only the ones where I add an 'AND' after my 'WHERE's fail. 2) Working with the while works perfectly with queries that do not contain '... AND ...' 3) Error reporting is on, PDO gives no exceptions on my query (or anything else) 4) Executing the query directly on the database does give what I want: SELECT * FROM user WHERE email = '[email protected]' AND wachtwoord = 'jurgen' I can stare at it all day long again (which I already did once, but I managed to work around the 'AND'), but maybe one of you can give me a helping hand. Thank you in advance. Jurgen

    Read the article

  • Is there a way to optimize this mysql query...?

    - by SpikETidE
    Hi Everyone... Say, I got these two tables.... Table 1 : Hotels hotel_id hotel_name 1 abc 2 xyz 3 efg Table 2 : Payments payment_id payment_date hotel_id total_amt comission p1 23-03-2010 1 100 10 p2 23-03-2010 2 50 5 p3 23-03-2010 2 200 25 p4 23-03-2010 1 40 2 Now, I need to get the following details from the two tables Given a particular date (say, 23-03-2010), the sum of the total_amt for each of the hotel for which a payment has been made on that particular date. All the rows that has the date 23-03-2010 ordered according to the hotel name A sample output is as follows... +------------+------------+------------+---------------+ | hotel_name | date | total_amt | commission | +------------+------------+------------+---------------+ | * abc | 23-03-2010 | 140 | 12 | +------------+------------+------------+---------------+ |+-----------+------------+------------+--------------+| || paymt_id | date | total_amt | commission || |+-----------+------------+------------+--------------+| || p1 | 23-03-2010 | 100 | 10 || |+-----------+------------+------------+--------------+| || p4 | 23-03-2010 | 40 | 2 || |+-----------+------------+------------+--------------+| +------------+------------+------------+---------------+ | * xyz | 23-03-2010 | 250 | 30 | +------------+------------+------------+---------------+ |+-----------+------------+------------+--------------+| || paymt_id | date | total_amt | commission || |+-----------+------------+------------+--------------+| || p2 | 23-03-2010 | 50 | 5 || |+-----------+------------+------------+--------------+| || p3 | 23-03-2010 | 200 | 25 || |+-----------+------------+------------+--------------+| +------------------------------------------------------+ Above the sample of the table that has to be printed... The idea is first to show the consolidated detail of each hotel, and when the '*' next to the hotel name is clicked the breakdown of the payment details will become visible... But that can be done by some jquery..!!! The table itself can be generated with php... Right now i am using two separate queries : One to get the sum of the amount and commission grouped by the hotel name. The next is to get the individual row for each entry having that date in the table. This is, of course, because grouping the records for calculating sum() returns only one row for each of the hotel with the sum of the amounts... Is there a way to combine these two queries into a single one and do the operation in a more optimized way...?? Hope i am being clear.. Thanks for your time and replies...

    Read the article

  • Django sphinx works only after app restart.

    - by Lhiash
    Hi, I've set up django-sphinx in my project, which works perfectly only for some time. Later it always returns empty result set. Surprisingly restarting django app fixes it. And search works again but again only for short time (or very limiter number of queries). Heres my sphinx.conf: source src_questions { # data source type = mysql sql_host = xxxxxx sql_user = xxxxxx #replace with your db username sql_pass = xxxxxx #replace with your db password sql_db = xxxxxx #replace with your db name # these two are optional sql_port = xxxxxx #sql_sock = /var/lib/mysql/mysql.sock # pre-query, executed before the main fetch query sql_query_pre = SET NAMES utf8 # main document fetch query sql_query = SELECT q.id AS id, q.title AS title, q.tagnames AS tags, q.html AS text, q.level AS level \ FROM question AS q \ WHERE q.deleted=0 \ # optional - used by command-line search utility to display document information sql_query_info = SELECT title, id, level FROM question WHERE id=$id sql_attr_uint = level } index questions { # which document source to index source = src_questions # this is path and index file name without extension # you may need to change this path or create this folder path = /home/rafal/core_index/index_questions # docinfo (ie. per-document attribute values) storage strategy docinfo = extern # morphology morphology = stem_en # stopwords file #stopwords = /var/data/sphinx/stopwords.txt # minimum word length min_word_len = 3 # uncomment next 2 lines to allow wildcard (*) searches min_infix_len = 1 enable_star = 1 # charset encoding type charset_type = utf-8 } # indexer settings indexer { # memory limit (default is 32M) mem_limit = 64M } # searchd settings searchd { # IP address on which search daemon will bind and accept # optional, default is to listen on all addresses, # ie. address = 0.0.0.0 address = 127.0.0.1 # port on which search daemon will listen port = 3312 # searchd run info is logged here - create or change the folder log = ../log/sphinx.log # all the search queries are logged here query_log = ../log/query.log # client read timeout, seconds read_timeout = 5 # maximum amount of children to fork max_children = 30 # a file which will contain searchd process ID pid_file = searchd.pid # maximum amount of matches this daemon would ever retrieve # from each index and serve to client max_matches = 1000 } and heres my search part from views.py: content = Question.search.query(keywords) if level: content = content.filter(level=level)#level is array of integers There are no errors in any logs, it just isnt returning any results. All help would be most appreciated.

    Read the article

  • Are Parameters really enough to prevent Sql injections?

    - by Rune Grimstad
    I've been preaching both to my colleagues and here on SO about the goodness of using parameters in SQL queries, especially in .NET applications. I've even gone so far as to promise them as giving immunity against SQL injection attacks. But I'm starting to wonder if this really is true. Are there any known SQL injection attacks that will be successfull against a parameterized query? Can you for example send a string that causes a buffer overflow on the server? There are of course other considerations to make to ensure that a web application is safe (like sanitizing user input and all that stuff) but now I am thinking of SQL injections. I'm especially interested in attacks against MsSQL 2005 and 2008 since they are my primary databases, but all databases are interesting. Edit: To clarify what I mean by parameters and parameterized queries. By using parameters I mean using "variables" instead of building the sql query in a string. So instead of doing this: SELECT * FROM Table WHERE Name = 'a name' We do this: SELECT * FROM Table WHERE Name = @Name and then set the value of the @Name parameter on the query / command object.

    Read the article

  • IntegrityError: foreign key violation upon delete

    - by Lukasz Korzybski
    I have Order and Shipment model. Shipment has a foreign key to Order. class Order(...): ... class Shipment() order = m.ForeignKey('Order') ... Now in one of my views I want do delete order object along with all related objects. So I invoke order.delete(). I have Django 1.0.4, PostgreSQL 8.4 and I use transaction middleware, so whole request is enclosed in single transaction. The problem is that upon order.delete() I get: ... File "/usr/local/lib/python2.6/dist-packages/django/db/backends/__init__.py", line 28, in _commit return self.connection.commit() IntegrityError: update or delete on table "main_order" violates foreign key constraint "main_shipment_order_id_fkey" on table "main_shipment" DETAIL: Key (id)=(45) is still referenced from table "main_shipment". I checked in connection.queries that proper queries are executed in proper order. First shipment is deleted, after that django executes delete on order row: {'time': '0.000', 'sql': 'DELETE FROM "main_shipment" WHERE "id" IN (17)'}, {'time': '0.000', 'sql': 'DELETE FROM "main_order" WHERE "id" IN (45)'} Foreign key have ON DELETE NO ACTION (default) and is initially deferred. I don't know why I get foreign key constraint violation. I also tried to register pre_delete signal and manually delete shipment objects before delete on order is called, but it resulted in the same error. I can change ON DELETE behaviour for this key in Postgres but it would be just a hack, I wonder if anyone has a better idea what's going on here. There is also a small detail, my Order model inherits from Cart model, so it actually doesn't have id field but cart_ptr_id and after DELETE on order is executed there is also DELETE on cart, but it seems unrelated? to the shipment-order problem so I simplified it in the example.

    Read the article

  • VS2008 DataSet Wizard doesn't match tables for updating

    - by James H
    Hi all, first question ever on this site. I've been having a real stubborn problem using Visual Studio 2008 and I'm hoping someone has figured this out before. I have 2 libraries and 1 project that use strongly typed datasets (MSSQL backend) that I generated using the "Configure DataSet with Wizard" option on in Data Sources. I've had them working just fine for awhile and I've written a lot of code in the non-designer file for the row classes. I've also specified a lot of custom queries using the dataset designer. This is all work I can't afford to loose. I've recently made some changes to re-organize my libraries which included changing the names of the libraries themselves. I also changed the connection string to point to a different database which is a development copy (same exact schema). Problem is now when I open up "Configure DataSet with Wizard" to pickup a new column I've added to one of the tables it no longer matches the tables correctly in the wizard. The wizard displays all of the tables in the database and none of them have check boxes next to them (ie: are not part of this dataset). Below those it shows all of the tables again but with red Xs and these are checked. Basically meaning that Visual Studio sees all of the tables it currently has in the DataSet and sees all of the tables in the database, but believes they are no longer the same and thus do not match! I've had this same thing happen quite awhile back and I think I just re-built the xsd from scratch and manually copied the code over and then had to redefine all of the custom queries I built in the dataset designer. That's not a good solution. I'm looking for 2 answers: 1. What causes this to happen and how to prevent it. 2. How do I fix this so that the wizard once again believes the tables in its xsd are the same tables that are in the database (yes, they have the exact same names still). Thanks.

    Read the article

  • Executing sequential stored procedures; works in query analyzer, doesn't in my .NET application

    - by evanmortland
    Hello, I have an audit record table that I am writing to. I am connecting to MyDb, which has a stored procedure called 'CreateAudit', which is a passthrough stored procedure to another database on the same machine called MyOther DB with a stored procedure called 'CreatedAudit' as well. In other words in MyDB I have CreateAudit, which does the following EXEC dbo.MyOtherDB.CreateAudit. I call the MyDb CreateAudit stored procedure from my application, using subsonic as the DAL. The first time I call it, I call it with the following (pseudocode): Result = CreateAudit(recordId, "Opened") One line after that, I call: Result2 = CreateAudit(recordId, "Closed") In my second stored procedure it is supposed to mark the record that was created by the CreateAudit(recordId, "Opened") with a status of closed. It works great if I run them independently of one another, but when they run in sequence in the application, the record is not marked as "Closed". When I run SQL profiler I see that both queries ran, and if I copy the queries out and run them from query analyzer the record gets marked as closed 100% of the time! When I run it from the application, about once every 20 times or so, the record is successfully marked closed - the other 19 times nothing happens, but I do not get an error! Is it possible for the .NET app to skip over the ouput from the first stored procedure and start executing the second stored procedure before the record in the first is created? When I add a "WAITFOR DELAY '00:00:00:003'" to the top of my stored procedure, the record is also closed 100% of the time. My head is spinning, any ideas why this is happening! Thanks for any responses, very interested in hearing how this can happen.

    Read the article

  • How to parse a custom XML-style error code response from a website

    - by user1870127
    I'm developing a program that queries and prints out open data from the local transit authority, which is returned in the form of an XML response. Normally, when there are buses scheduled to run in the next few hours (and in other typical situations), the XML response generated by the page is handled correctly by the java.net.URLConnection.getInputStream() function, and I am able to print the individual results afterwards. The problem is when the buses are NOT running, or when some other problem with my queries develops after it is sent to the transit authority's web server. When the authority developed their service, they came up with their own unique error response codes, which are also sent as XMLs. For example, one of these error messages might look like this: <Error xmlns:i="http://www.w3.org/2001/XMLSchema-instance"> <Code>3005</Code> <Message>Sorry, no stop estimates found for given values.</Message> </Error> (This code and similar is all that I receive from the transit authority in such situations.) However, it appears that URLConnection.getInputStream() and some of its siblings are unable to interpret this custom code as a "valid" response that I can handle and print out as an error message. Instead, they give me a more generic HTTP/1.1 404 Not Found error. This problem cascades into my program which then prints out a java.io.FileNotFoundException error pointing to the offending input stream. My question is therefore two-fold: 1. Is there a way to retrieve, parse, and print a custom XML-formatted error code sent by a web service using the plugins that are available in Java? 2. If the above is not possible, what other tools should I use or develop to handle such custom codes as described?

    Read the article

  • Multiple threads modifying a collection in Java??

    - by posdef
    Hi, The project I am working on requires a whole bunch of queries towards a database. In principle there are two types of queries I am using: read from excel file, check for a couple of parameters and do a query for hits in the database. These hits are then registered as a series of custom classes. Any hit may (and most likely will) occur more than once so this part of the code checks and updates the occurrence in a custom list implementation that extends ArrayList. for each hit found, do a detail query and parse the output, so that the classes created in (I) get detailed info. I figured I would use multiple threads to optimize time-wise. However I can't really come up with a good way to solve the problem that occurs with the collection these items are stored in. To elaborate a little bit; throughout the execution objects are supposed to be modified by both (I) and (II). I deliberately didn't c/p any code, as it would be big chunks of code to make any sense.. I hope it make some sense with the description above. Thanks,

    Read the article

  • MySQL database design question

    - by Greelmo
    I'm trying to weigh the pros and cons of a database design, and would like to get some feedback as to the best approach. Here is the situation: I have users of my system that have only a few required items (username, password). They can then supply a lot of optional information. This optional information continues to grow as the system grows, so I want to do it in such a way that adding new optional information is easy. Currently, I have a separate table for each piece of information. For example, there's a table called 'names' that holds 'user_id', 'first_name', and 'last_name'. There's 'address', 'occupation', etc. You get the drift. In most cases, when I talk to my database, I'm looking only for users with one particular qualifier (name, address, etc.). However, there are instances when I want to see what information a user has set. The 'edit account' page, for example, must run queries for each piece of information it wants. Is this wasteful? Is there a way I can structure my queries or my database to make it so I never have to do one query for each piece of information like that without getting my tables to huge? If i want to add 'marital status', how hard will that be if I don't have a one-table-per-attribute system? Thanks in advance.

    Read the article

  • Is there a standard for storing normalized phone numbers in a database?

    - by Eric Z Beard
    What is a good data structure for storing phone numbers in database fields? I'm looking for something that is flexible enough to handle international numbers, and also something that allows the various parts of the number to be queried efficiently. [Edit] Just to clarify the use case here: I currently store numbers in a single varchar field, and I leave them just as the customer entered them. Then, when the number is needed by code, I normalize it. The problem is that if I want to query a few million rows to find matching phone numbers, it involves a function, like where dbo.f_normalizenum(num1) = dbo.f_normalizenum(num2) which is terribly inefficient. Also queries that are looking for things like the area code become extremely tricky when it's just a single varchar field. [Edit] People have made lots of good suggestions here, thanks! As an update, here is what I'm doing now: I still store numbers exactly as they were entered, in a varchar field, but instead of normalizing things at query time, I have a trigger that does all that work as records are inserted or updated. So I have ints or bigints for any parts that I need to query, and those fields are indexed to make queries run faster.

    Read the article

  • Foreign/accented characters in sql query

    - by FromCanada
    I'm using Java and Spring's JdbcTemplate class to build an SQL query in Java that queries a Postgres database. However, I'm having trouble executing queries that contain foreign/accented characters. For example the (trimmed) code: JdbcTemplate select = new JdbcTemplate( postgresDatabase ); String query = "SELECT id FROM province WHERE name = 'Ontario';"; Integer id = select.queryForObject( query, Integer.class ); will retrieve the province id, but if instead I did name = 'Québec' then the query fails to return any results (this value is in the database so the problem isn't that it's missing). I believe the source of the problem is that the database I am required to use has the default client encoding set to SQL_ASCII, which according to this prevents automatic character set conversions. (The Java environments encoding is set to 'UTF-8' while I'm told the database uses 'LATIN1' / 'ISO-8859-1') I was able to manually indicate the encoding when the resultSets contained values with foreign characters as a solution to a previous problem with a similar nature. Ex: String provinceName = new String ( resultSet.getBytes( "name" ), "ISO-8859-1" ); But now that the foreign characters are part of the query itself this approach hasn't been successful. (I suppose since the query has to be saved in a String before being executed anyway, breaking it down into bytes and then changing the encoding only muddles the characters further.) Is there a way around this without having to change the properties of the database or reconstruct it? PostScript: I found this function on StackOverflow when making up a title, it didn't seem to work (I might not have used it correctly, but even if it did work it doesn't seem like it could be the best solution.):

    Read the article

  • Need a tool to search large structure text documents for words, phrases and related phrases

    - by pitosalas
    I have to keep up with structured documents containing things such as requests for proposals, government program reports, threat models and all kinds of things like that. They are in techno-legalese as I would call them: highly structured, with section numbering and 3, 4 and 5 levels of nesting. All in English I need a more efficient way to locate those paragraphs of nuggets that matter to me. So what I’d like is kind of a local document index/repository, that would allow me to have some standing queries and easily locate sections in documents that talk about my queries. Here’s an example: I’d like to load in 10 large PDF files, each of say 100 pages. Each PDF contains English text, formatted very nicely into paragraphs and sections. I’d like to specify that I am interested in “blogging platforms”, “weaknesses in Ruby”, “localization and internationalization” Ideally then look at a list that showed the section of text, the name of the document, and other information that seemed to be related to and/or include the words and phrases I specified. I am sure something like this exists. I would call it something like document indexing, document comprehension or structured searching.

    Read the article

  • Do complex JOINs cause high coupling and maintenance problems ?

    - by ashkan.kh.nazary
    Our project has ~40 tables with complex relations.A colleague believes in using long join queries which enforces me to learn about tables outside of my module but I think I should not concern about tables not directly related to my module and use data access functions (written by those responsible for other modules) when I need data from them. Let me clarify: I am responsible for the ContactVendor module which enables the customers to contact the vendor and start a conversation about some specific product. Products module has it's own complex tables and relations with functions that encapsulate details (for example i18n, activation, product availability etc ...). Now I need to show the product title of some product related to some conversation between the vendor and customers. I may either write a long query that retrieves the product info along with conversation stuff in one shot (which enforces me to learn about Product tables) OR I may pass the relevant product_id to the get_product_info(int) function. First approach is obviously demanding and introduces many bad practices and things I normally consider fault in programming. The problem with the second approach seems to be the countless mini queries these access functions cause and performance loss is a concern when a loop tries to fetch product titles for 100 products using functions that each perform a separate query. So I'm stuck between "don't code to the implementation, code to interface" and performance. What is the right way of doing things ? UPDATE: I'm specially concerned about possible future modifications to those tables outside of my module. What if the Products module decided to change the way they are doing things? or for some reason modify the schema? It means some other modules would break or malfunction until the change is integrated to them. The usual ripple effect problem.

    Read the article

  • Does complex JOINs causes high coupling and maintenance problems ?

    - by ashkan.kh.nazary
    Our project has ~40 tables with complex relations.A colleague believes in using long join queries which enforces me to learn about tables outside of my module but I think I should not concern about tables not directly related to my module and use data access functions (written by those responsible for other modules) when I need data from them. Let me clarify: I am responsible for the ContactVendor module which enables the customers to contact the vendor and start a conversation about some specific product. Products module has it's own complex tables and relations with functions that encapsulate details (for example i18n, activation, product availability etc ...). Now I need to show the product title of some product related to some conversation between the vendor and customers. I may either write a long query that retrieves the product info along with conversation stuff in one shot (which enforces me to learn about Product tables) OR I may pass the relevant product_id to the get_product_info(int) function. First approach is obviously demanding and introduces many bad practices and things I normally consider fault in programming. The problem with the second approach seems to be the countless mini queries these access functions cause and performance loss is a concern when a loop tries to fetch product titles for 100 products using functions that each perform a separate query. So I'm stuck between "don't code to the implementation, code to interface" and performance. What is the right way of doing things ? UPDATE: I'm specially concerned about possible future modifications to those tables outside of my module. What if the Products module decided to change the way they are doing things? or for some reason modify the schema? It means some other modules would break or malfunction until the change is integrated to them. The usual ripple effect problem.

    Read the article

  • Project management: Implementing custom errors in VS compilation process

    - by David Lively
    Like many architects, I've developed coding standards through years of experience to which I expect my developers to adhere. This is especially a problem with the crowd that believes that three or four years of experience makes you a senior-level developer.Approaching this as a training and code review issue has generated limited success. So, I was thinking that it would be great to be able to add custom compile-time errors to the build process to more strictly enforce this and other guidelines. For instance, we use stored procedures for ALL database access, which provides procedure-level security, db encapsulation (table structure is hidden from the app), and other benefits. (Note: I am not interested in starting a debate about this.) Some developers prefer inline SQL or parametrized queries, and that's fine - on their own time and own projects. I'd like a way to add a compilation check that finds, say, anything that looks like string sql = "insert into some_table (col1,col2) values (@col1, @col2);" and generates an error or, in certain circumstances, a warning, with a message like Inline SQL and parametrized queries are not permitted. Or, if they use the var keyword var x = new MyClass(); Variable definitions must be explicitly typed. Do Visual Studio and MSBuild provide a way to add this functionality? I'm thinking that I could use a regular expression to find unacceptable code and generate the correct error, but I'm not sure what, from a performance standpoint, is the best way to to integrate this into the build process. We could add a pre- or post-build step to run a custom EXE, but how can I return line- and file-specifc errors? Also, I'd like this to run after compilation of each file, rather than post-link. Is a regex the best way to perform this type of pattern matching, or should I go crazy and run the code through a C# parser, which would allow node-level validation via the parse tree? I'd appreciate suggestions and tales of prior experience.

    Read the article

  • How to export Oracle statistics

    - by A_M
    Hi, I am writing some new SQL queries and want to check the query plans that the Oracle query optimiser would come up with in production. My development database doesn't have anything like the data volumes of the production database. How can I export database statistics from a production database and re-import them into a development database? I don't have access to the production database, so I can't simply generate explain plans on production without going through a third party hosting organisation. This is painful. So I want a local database which is in some way representative of production on which I can try out different things. Also, this is for a legacy application. I'd like to "improve" the schema, by adding appropriate indexes. constraints, etc. I need to do this in my development database first, before rolling out to test and production. If I add an index and re-generate statistics in development, then the statistics will be generated around the development data volumes, which makes it difficult to assess the impact my changes on production. Does anyone have any tips on how to deal with this? Or is it just a case of fixing unexpected behaviour once we've discovered it on production? I do have a staging database with production volumes, but again I have to go through a third party to run queries against this, which is painful. So I'm looking for ways to cut out the middle man as much as possible. All this is using Oracle 9i. Thanks.

    Read the article

  • Requested operation requires an OLE DB Session object... - Connecting Excel to SQL server via ADO

    - by Frank V
    I'm attempting to take Excel 2003 and connect it to SQL Server 2000 to run a few dynamicly generated SQL Queries which ultimately filling certain cells. I'm attempting to do this via VBA via ADO (I've tried 2.8 to 2.0) but I'm getting an error while setting the ActiveConnection variable which is inside the ADODB.Connection object. I need to resolve this pretty quick... Requested operation requires an OLE DB Session object, which is not supported by the current provider. I'm honestly not sure what this error means and right now I don't care. How can get this connection to succeed so that I can run my queries? Here is my VB code: Dim SQL As String, RetValue As String SQL = " select top 1 DateTimeValue from SrcTable where x='value' " 'Not the real SQL RetValue = "" Dim RS As ADODB.Recordset Dim Con As New ADODB.Connection Dim Cmd As New ADODB.Command Con.ConnectionString = "Provider=sqloledb;DRIVER=SQL Server;Data Source=Server\Instance;Initial Catalog=MyDB_DC;User Id=<UserName>;Password=<Password>;" Con.CommandTimeout = (60 * 30) Set Cmd.ActiveConnection = Con ''Error occurs here. ' I'm not sure if the rest is right. I've just coded it. Can't get past the line above. Cmd.CommandText = SQL Cmd.CommandType = adCmdText Con.Open Set RS = Cmd.Execute() If Not RS.EOF Then RetValue = RS(0).Value Debug.Print "RetValue is: " & RetValue End If Con.Close I imagine something is wrong with the connection string but I've tried over a dozen variations. Now I'm just shooting in the dark.... Note/Update: To make matters more confusing, if I Google for the error quote above, I get a lot of hits back but nothing seems relevant or I'm not sure what information is relevant.... I've got the VBA code in "Sheet1" under "Microsoft Excel Objects." I've done this before but usually put things in a module. Could this make a difference?

    Read the article

  • Problem with Active Record

    - by kshchepelin
    Hello everyone. Lets assume we have a User model. And user can plan some activities. The number of types of activities is about 50. All activities have common properties, such as start_time, end_time, user_id, etc. But each of them has some unique properties. Now we have each activity living in its own table in DB. And thats why we have such terrible sql queries like SELECT * FROM `first_activities_table` WHERE (`first_activity`.`id` IN (17,18)) SELECT * FROM `second_activities_table` WHERE (`second_activity`.`id` = 17) ..... SELECT * FROM `n_activities_table` WHERE (`n_activity`.`id` = 44) About 50 queries. That's terrible. There are different ways to solve this. Choose the activity type with the biggest number of properties, create the table 'Activities' and have STI model. But this way we must name our columns in uncomfortable way and often the record in that table would have some NULL fields. Also STI model, but having columns, common for all of activity types and some blob column with serialized properties. But we have to do some search on activities - there can be a problem. And serialization is quite slow. Please help me dealing with this. Maybe my problem has quite different solution that will fit my needs. Thanks for help.

    Read the article

  • How to create more complex Lucene query strings?

    - by boris callens
    This question is a spin-off from this question. My inquiry is two-fold, but because both are related I think it is a good idea to put them together. How to programmatically create queries. I know I could start creating strings and get that string parsed with the query parser. But as I gather bits and pieces of information from other resources, there is a programattical way to do this. What are the syntax rules for the Lucene queries? --EDIT-- I'll give a requirement example for a query I would like to make: Say I have 5 fields: First Name Last Name Age Address Everything All fields are optional, the last field should search over all the other fields. I go over every field and see if it's IsNullOrEmpty(). If it's not, I would like to append a part of my query so it adds the relevant search part. First name and last name should be exact matches and have more weight then the other fields. Age is a string and should exact match. Address can varry in order. Everything can also varry in order. How should I go about this?

    Read the article

  • FreeTDS runs out of memory from DBD::Sybase

    - by skiphoppy
    When I add client charset = UTF-8 to my freetds.conf file, my DBD::Sybase program emits: Out of memory! and terminates. This happens when I call execute() on an SQL query statement that returns any ntext fields. I can return numeric data, datetimes, and nvarchars just fine, but whenever one of the output fields is ntext, I get this error. All these queries work perfectly fine without the UTF-8 setting, but I do need to handle some characters that throw warnings under the default character set. (See related question.) The error message is not formatted the same way other DBD::Sybase error messages seem to be formatted. I do get a message that a rollback() is being issued, though. (My false AutoCommit flag is being honored.) I think I read somewhere that FreeTDS uses the iconv program to convert between character sets; is it possible that this message is being emitted from iconv? If I execute the same query with the same freetds.conf settings in tsql (FreeTDS's command-line SQL shell), I don't get the error. I'm connecting to SQL Server. What do I need to do to get these queries to return successfully?

    Read the article

< Previous Page | 63 64 65 66 67 68 69 70 71 72 73 74  | Next Page >