Search Results

Search found 25852 results on 1035 pages for 'linq query syntax'.

Page 96/1035 | < Previous Page | 92 93 94 95 96 97 98 99 100 101 102 103  | Next Page >

  • SQL query to get latest record for all distinct items in a table

    - by David Buckley
    I have a table of all sales defined like: mysql> describe saledata; +-------------------+---------------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------------------+---------------------+------+-----+---------+-------+ | SaleDate | datetime | NO | | NULL | | | StoreID | bigint(20) unsigned | NO | | NULL | | | Quantity | int(10) unsigned | NO | | NULL | | | Price | decimal(19,4) | NO | | NULL | | | ItemID | bigint(20) unsigned | NO | | NULL | | +-------------------+---------------------+------+-----+---------+-------+ I need to get the last sale price for all items (as the price may change). I know I can run a query like: SELECT price FROM saledata WHERE itemID = 1234 AND storeID = 111 ORDER BY saledate DESC LIMIT 1 However, I want to be able to get the last sale price for all items (the ItemIDs are stored in a separate item table) and insert them into a separate table. How can I get this data? I've tried queries like this: SELECT storeID, itemID, price FROM saledata WHERE itemID IN (SELECT itemID from itemmap) ORDER BY saledate DESC LIMIT 1 and then wrap that into an insert, but it's not getting the proper data. Is there one query I can run to get the last price for each item and insert that into a table defined like: mysql> describe lastsale; +-------------------+---------------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------------------+---------------------+------+-----+---------+-------+ | StoreID | bigint(20) unsigned | NO | | NULL | | | Price | decimal(19,4) | NO | | NULL | | | ItemID | bigint(20) unsigned | NO | | NULL | | +-------------------+---------------------+------+-----+---------+-------+

    Read the article

  • MySQL LIMIT 1 but query 15 rows?

    - by Ian
    Basically what I'm trying to do is compare the ID's of rows against 15 results in MySQL, eliminating all but 1 (using NOT IN) and then pull that result. Now normally this would be fine by itself, however the order of the 15 rows I'm doing the SQL query for are constantly changing based on a ranking, so there is a possibility that between the time the ranking updates, and the ajax request (which I submit the ID's for NOT IN) more than just one ID has changed, which would of course bring back more than one row which I do not want. So in short, is there a way in which I can query 15 rows, but only return one? Without having to run two separate queries. Any help is appreciated, thank you. EXAMPLE: Say I have 7 items in my database, and I'm displaying 5 on the page to the user. These are what are being displayed to the user: Apple Orange Kiwi Banana Grape But in the database I also have Peach Blackberry Now what I want to do is if the user deletes an item from their list, it will add another item (based on a ranking they have) Now the issue is, in order to know what they have on their list at the moment I send the remaining items to the database (say they deleted Kiwi, I would send Apple, Orange, Banana, and Grape) So now I select the highest ranked 5 items from are remaining six items, make sure they are not the ones already displayed on the page, and then add the new one to list (either Peach or Blackberry) All good and well, except that if both peach and blackberry now outrank grape, then I will be returning two results instead of just one. Because it would've searched... Apple Orange Banana Peach Blackberry and excluded... Apple Orange Banana Grape Which leaves us with both Peach and Blackberry, instead of just Peach or Blackberry

    Read the article

  • Fix N+1 query in "declarative_authorization" gem using gem "bullet"

    - by makaroni4
    Currently I am working on one big web application and to make it work faster I decided to refactor all N+1 queries (to decrease number of requests to database, http://rails-bestpractices.com/posts/29-fix-n-1-queries). So I installed gem "bullet" which doesn`t work with Rails 3.1.1 now (you can use fork from https://github.com/flyerhzm/bullet). When using declarative_authorization gem on each page I get same alerts: N+1 Query detected Role => [:permissions] Add to your finder: :include => [:permissions] N+1 Query detected Permission => [:permission_rules] Add to your finder: :include => [:permission_rules] CACHE (0.0ms) SELECT "roles".* FROM "roles" CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 1 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 2 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 3 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 4 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 6 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 7 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 8 CACHE (0.0ms) SELECT "permission_rules".* FROM "permission_rules" INNER JOIN "permission_rules_permissions" ON "permission_rules"."id" = "permission_rules_permissions"."permission_rule_id" WHERE "permission_rules_permissions"."permission_id" = 30 CACHE (0.0ms) SELECT "permission_rules".* FROM "permission_rules" INNER JOIN "permission_rules_permissions" ON "permission_rules"."id" = "permission_rules_permissions"."permission_rule_id" WHERE "permission_rules_permissions"."permission_id" = 31 ... Could you please help me with that and to make this queries faster?

    Read the article

  • build SQL query string using user input

    - by user175084
    i have to make a string by using the values which the user selects on the webpage suppose i need to display files for multiple machines with differnt search criteria.. i currently use this code: DataTable dt = new DataTable(); SqlConnection connection = new SqlConnection(); connection.ConnectionString = ConfigurationManager.ConnectionStrings["DBConnectionString"].ConnectionString; connection.Open(); SqlCommand sqlCmd = new SqlCommand("SELECT FileID FROM Files WHERE MachineID=@machineID and date= @date", connection); SqlDataAdapter sqlDa = new SqlDataAdapter(sqlCmd); sqlCmd.Parameters.AddWithValue("@machineID", machineID); sqlCmd.Parameters.AddWithValue("@date", date); sqlDa.Fill(dt); now this is fixed query where the user just has one machine and just selects one date... i want to make a query in which the user has multiple search options like type or size if he wants depending on what he selects also if he can select multiple machines.. SELECT FileID FROM Files WHERE (MachineID=@machineID1 or MachineID = @machineID2...) and (date= @date and size=@size and type=@type... ) all of this happens in runtime... other wise i have to create a for loop to put multiple machines one by one... and have multiple queries depending on the case the user selected... this is quiet interesting and i could use some help... thanks

    Read the article

  • help with delete where not in query

    - by kralco626
    I have a lookup table (##lookup). I know it's bad design because I'm duplicating data, but it speeds up my queries tremendously. I have a query that populates this table insert into ##lookup select distinct col1,col2,... from table1...join...etc... I would like to simulate this behavior: delete from ##lookup insert into ##lookup select distinct col1,col2,... from table1...join...etc... This would clearly update the table correctly. But this is a lot of inserting and deleting. It messes with my indexes and locks up the table for selecting from. This table could also be updated by something like: delete from ##lookup where not in (select distinct col1,col2,... from table1...join...etc...) insert into ##lookup (select distinct col1,col2,... from table1...join...etc...) except if it is already in the table The second way may take longer, but I can say "with no lock" and I will be able to select from the table. Any ideas on how to write the query the second way?

    Read the article

  • How to loop through an array return from the Query of Mysql

    - by Jerry
    This might be easy for you guys but i could't get it. I have a php class that query the database and return the query result. I assign the result to an array and wants to use it on my main.php script. I have tried to use echo $var[0] or echo $var[1] but the output are 'array' instead of my value. Anyone can help me about this issue? Thanks a lot! My php class <?php class teamQuery { function teamQuery(){ } function getAllTeam(){ $connection = mysql_connect(DB_SERVER,DB_USER,DB_PASS); if (!$connection) { die("Database connection failed: " . mysql_error()); } $db_select = mysql_select_db(DB_NAME,$connection); if (!$db_select) { die("Database selection failed: " . mysql_error()); } $teamQuery=mysql_query("SELECT * FROM team", $connection); if (!$teamQuery){ die("database has errors: ".mysql_error()); } $ret = array(); while($row=mysql_fetch_array($teamQuery)){ $ret[]=$row; } mysql_free_result($teamQuery); return $ret; } } ?> My php on the main.php $getTeam=new teamQuery(); $team=$getTeam->getAllTeam(); //echo $team[0] or team[1] output 'array' string! // while($team){ // do something } can't work either // How to loop through the values?? Thanks!

    Read the article

  • Optimize SQL query (Facebook-like application)

    - by fabriciols
    My application is similar to Facebook, and I'm trying to optimize the query that get user records. The user records are that he as src ou dst. The src is in usermuralentry directly, the dst list are in usermuralentry_user. So, a entry can have one src and many dst. I have those tables: mysql> desc usermuralentry ; +-----------------+------------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-----------------+------------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | user_src_id | int(11) | NO | MUL | NULL | | | private | tinyint(1) | NO | | NULL | | | content | longtext | NO | | NULL | | | date | datetime | NO | | NULL | | | last_update | datetime | NO | | NULL | | +-----------------+------------------+------+-----+---------+----------------+ 10 rows in set (0.10 sec) mysql> desc usermuralentry_user ; +-------------------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------------+---------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | usermuralentry_id | int(11) | NO | MUL | NULL | | | userinfo_id | int(11) | NO | MUL | NULL | | +-------------------+---------+------+-----+---------+----------------+ 3 rows in set (0.00 sec) And the following query to retrieve information from two users. mysql> explain SELECT * FROM usermuralentry AS a , usermuralentry_user AS b WHERE a.user_src_id IN ( 1, 2 ) OR ( a.id = b.usermuralentry_id AND b.userinfo_id IN ( 1, 2 ) ); +----+-------------+-------+------+-------------------------------------------------------------------------------------------+------+---------+------+---------+------------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+------+-------------------------------------------------------------------------------------------+------+---------+------+---------+------------------------------------------------+ | 1 | SIMPLE | b | ALL | usermuralentry_id,usermuralentry_user_bcd7114e,usermuralentry_user_6b192ca7 | NULL | NULL | NULL | 147188 | | | 1 | SIMPLE | a | ALL | PRIMARY | NULL | NULL | NULL | 1371289 | Range checked for each record (index map: 0x1) | +----+-------------+-------+------+-------------------------------------------------------------------------------------------+------+---------+------+---------+------------------------------------------------+ 2 rows in set (0.00 sec) but it is taking A LOT of time... Some tips to optimize? Can the table schema be better in my application?

    Read the article

  • SQL Server 05, which is optimal, LIKE %<term>% or CONTAINS() for searching large column

    - by Spud1
    I've got a function written by another developer which I am trying to modify for a slightly different use. It is used by a SP to check if a certain phrase exists in a text document stored in the DB, and returns 1 if the value is found or 0 if its not. This is the query: SELECT @mres=1 from documents where id=@DocumentID and contains(text, @search_term) The document contains mostly XML, and the search_term is a GUID formatted as an nvarchar(40). This seems to run quite slowly to me (taking 5-6 seconds to execute this part of the process), but in the same script file there is also this version of the above, commented out. SELECT @mres=1 from documents where id=@DocumentID and textlike '%' + @search_term + '%' This version runs MUCH quicker, taking 4ms compared to 15ms for the first example. So, my question is why use the first over the second? I assume this developer (who is no longer working with me) had a good reason, but at the moment I am struggling to find it.. Is it possibly something to do with the full text indexing? (this is a dev DB I am working with, so the production version may have better indexing..) I am not that clued up on FTI really so not quite sure at the moment. Thoughts/ideas?

    Read the article

  • SQL SERVER – DMV – sys.dm_exec_query_optimizer_info – Statistics of Optimizer

    - by pinaldave
    Incredibly, SQL Server has so much information to share with us. Every single day, I am amazed with this SQL Server technology. Sometimes I find several interesting information by just querying few of the DMV. And when I present this info in front of my client during performance tuning consultancy, they are surprised with my findings. Today, I am going to share one of the hidden gems of DMV with you, the one which I frequently use to understand what’s going on under the hood of SQL Server. SQL Server keeps the record of most of the operations of the Query Optimizer. We can learn many interesting details about the optimizer which can be utilized to improve the performance of server. SELECT * FROM sys.dm_exec_query_optimizer_info WHERE counter IN ('optimizations', 'elapsed time','final cost', 'insert stmt','delete stmt','update stmt', 'merge stmt','contains subquery','tables', 'hints','order hint','join hint', 'view reference','remote query','maximum DOP', 'maximum recursion level','indexed views loaded', 'indexed views matched','indexed views used', 'indexed views updated','dynamic cursor request', 'fast forward cursor request') All occurrence values are cumulative and are set to 0 at system restart. All values for value fields are set to NULL at system restart. I have removed a few of the internal counters from the script above, and kept only documented details. Let us check the result of the above query. As you can see, there is so much vital information that is revealed in above query. I can easily say so many things about how many times Optimizer was triggered and what the average time taken by it to optimize my queries was. Additionally, I can also determine how many times update, insert or delete statements were optimized. I was able to quickly figure out that my client was overusing the Query Hints using this dynamic management view. If you have been reading my blog, I am sure you are aware of my series related to SQL Server Views SQL SERVER – The Limitations of the Views – Eleven and more…. With this, I can take a quick look and figure out how many times Views were used in various solutions within the query. Moreover, you can easily know what fraction of the optimizations has been involved in tuning server. For example, the following query would tell me, in total optimizations, what the fraction of time View was “reference“. As this View also includes system Views and DMVs, the number is a bit higher on my machine. SELECT (SELECT CAST (occurrence AS FLOAT) FROM sys.dm_exec_query_optimizer_info WHERE counter = 'view reference') / (SELECT CAST (occurrence AS FLOAT) FROM sys.dm_exec_query_optimizer_info WHERE counter = 'optimizations') AS ViewReferencedFraction Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL DMV, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

    Read the article

  • SQL SERVER – Introduction to FIRST _VALUE and LAST_VALUE – Analytic Functions Introduced in SQL Server 2012

    - by pinaldave
    SQL Server 2012 introduces new analytical functions FIRST_VALUE() and LAST_VALUE(). This function returns first and last value from the list. It will be very difficult to explain this in words so I’d like to attempt to explain its function through a brief example. Instead of creating a new table, I will be using the AdventureWorks sample database as most developers use that for experiment purposes. Now let’s have fun following query: USE AdventureWorks GO SELECT s.SalesOrderID,s.SalesOrderDetailID,s.OrderQty, FIRST_VALUE(SalesOrderDetailID) OVER (ORDER BY SalesOrderDetailID) FstValue, LAST_VALUE(SalesOrderDetailID) OVER (ORDER BY SalesOrderDetailID) LstValue FROM Sales.SalesOrderDetail s WHERE SalesOrderID IN (43670, 43669, 43667, 43663) ORDER BY s.SalesOrderID,s.SalesOrderDetailID,s.OrderQty GO The above query will give us the following result: What’s the most interesting thing here is that as we go from row 1 to row 10, the value of the FIRST_VALUE() remains the same but the value of the LAST_VALUE is increasing. The reason behind this is that as we progress in every line – considering that line and all the other lines before it, the last value will be of the row where we are currently looking at. To fully understand this statement, see the following figure: This may be useful in some cases; but not always. However, when we use the same thing with PARTITION BY, the same query starts showing the result which can be easily used in analytical algorithms and needs. Let us have fun through the following query: Let us fun following query. USE AdventureWorks GO SELECT s.SalesOrderID,s.SalesOrderDetailID,s.OrderQty, FIRST_VALUE(SalesOrderDetailID) OVER (PARTITION BY SalesOrderID ORDER BY SalesOrderDetailID) FstValue, LAST_VALUE(SalesOrderDetailID) OVER (PARTITION BY SalesOrderID ORDER BY SalesOrderDetailID) LstValue FROM Sales.SalesOrderDetail s WHERE SalesOrderID IN (43670, 43669, 43667, 43663) ORDER BY s.SalesOrderID,s.SalesOrderDetailID,s.OrderQty GO The above query will give us the following result: Let us understand how PARTITION BY windows the resultset. I have used PARTITION BY SalesOrderID in my query. This will create small windows of the resultset from the original resultset and will follow the logic or FIRST_VALUE and LAST_VALUE in this resultset. Well, this is just an introduction to these functions. In the future blog posts we will go deeper to discuss the usage of these two functions. By the way, these functions can be applied over VARCHAR fields as well and are not limited to the numeric field only. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Function, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

    Read the article

  • MySQL query, 2 similar servers, 2 minute difference in execution times

    - by mr12086
    I had a similar question on stack overflow, but it seems to be more server/mysql setup related than coding. The queries below all execute instantly on our development server where as they can take upto 2 minutes 20 seconds. The query execution time seems to be affected by home ambiguous the LIKE string's are. If they closely match a country that has few matches it will take less time, and if you use something like 'ge' for germany - it will take longer to execute. But this doesn't always work out like that, at times its quite erratic. Sending data appears to be the culprit but why and what does that mean. Also memory on production looks to be quite low (free memory)? Production: Intel Quad Xeon E3-1220 3.1GHz 4GB DDR3 2x 1TB SATA in RAID1 Network speed 100Mb Ubuntu Development Intel Core i3-2100, 2C/4T, 3.10GHz 500 GB SATA - No RAID 4GB DDR3 UPDATE 2 : mysqltuner output: [prod] -------- General Statistics -------------------------------------------------- [--] Skipped version check for MySQLTuner script [OK] Currently running supported MySQL version 5.1.61-0ubuntu0.10.04.1 [OK] Operating on 64-bit architecture -------- Storage Engine Statistics ------------------------------------------- [--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster [--] Data in MyISAM tables: 103M (Tables: 180) [--] Data in InnoDB tables: 491M (Tables: 19) [!!] Total fragmented tables: 38 -------- Security Recommendations ------------------------------------------- [OK] All database users have passwords assigned -------- Performance Metrics ------------------------------------------------- [--] Up for: 77d 4h 6m 1s (53M q [7.968 qps], 14M conn, TX: 87B, RX: 12B) [--] Reads / Writes: 98% / 2% [--] Total buffers: 58.0M global + 2.7M per thread (151 max threads) [OK] Maximum possible memory usage: 463.8M (11% of installed RAM) [OK] Slow queries: 0% (12K/53M) [OK] Highest usage of available connections: 22% (34/151) [OK] Key buffer size / total MyISAM indexes: 16.0M/10.6M [OK] Key buffer hit rate: 98.7% (162M cached / 2M reads) [OK] Query cache efficiency: 20.7% (7M cached / 36M selects) [!!] Query cache prunes per day: 3934 [OK] Sorts requiring temporary tables: 1% (3K temp sorts / 230K sorts) [!!] Joins performed without indexes: 71068 [OK] Temporary tables created on disk: 24% (3M on disk / 13M total) [OK] Thread cache hit rate: 99% (690 created / 14M connections) [!!] Table cache hit rate: 0% (64 open / 85M opened) [OK] Open file limit used: 12% (128/1K) [OK] Table locks acquired immediately: 99% (16M immediate / 16M locks) [!!] InnoDB data size / buffer pool: 491.9M/8.0M -------- Recommendations ----------------------------------------------------- General recommendations: Run OPTIMIZE TABLE to defragment tables for better performance Enable the slow query log to troubleshoot bad queries Adjust your join queries to always utilize indexes Increase table_cache gradually to avoid file descriptor limits Variables to adjust: query_cache_size (> 16M) join_buffer_size (> 128.0K, or always use indexes with joins) table_cache (> 64) innodb_buffer_pool_size (>= 491M) [dev] -------- General Statistics -------------------------------------------------- [--] Skipped version check for MySQLTuner script [OK] Currently running supported MySQL version 5.1.62-0ubuntu0.11.10.1 [!!] Switch to 64-bit OS - MySQL cannot currently use all of your RAM -------- Storage Engine Statistics ------------------------------------------- [--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster [--] Data in MyISAM tables: 185M (Tables: 632) [--] Data in InnoDB tables: 967M (Tables: 38) [!!] Total fragmented tables: 73 -------- Security Recommendations ------------------------------------------- [OK] All database users have passwords assigned -------- Performance Metrics ------------------------------------------------- [--] Up for: 1d 2h 26m 9s (5K q [0.058 qps], 1K conn, TX: 4M, RX: 1M) [--] Reads / Writes: 99% / 1% [--] Total buffers: 58.0M global + 2.7M per thread (151 max threads) [OK] Maximum possible memory usage: 463.8M (11% of installed RAM) [OK] Slow queries: 0% (0/5K) [OK] Highest usage of available connections: 1% (2/151) [OK] Key buffer size / total MyISAM indexes: 16.0M/18.6M [OK] Key buffer hit rate: 99.9% (60K cached / 36 reads) [OK] Query cache efficiency: 44.5% (1K cached / 2K selects) [OK] Query cache prunes per day: 0 [OK] Sorts requiring temporary tables: 0% (0 temp sorts / 44 sorts) [OK] Temporary tables created on disk: 24% (162 on disk / 666 total) [OK] Thread cache hit rate: 99% (2 created / 1K connections) [!!] Table cache hit rate: 1% (64 open / 4K opened) [OK] Open file limit used: 8% (88/1K) [OK] Table locks acquired immediately: 100% (1K immediate / 1K locks) [!!] InnoDB data size / buffer pool: 967.7M/8.0M -------- Recommendations ----------------------------------------------------- General recommendations: Run OPTIMIZE TABLE to defragment tables for better performance Enable the slow query log to troubleshoot bad queries Increase table_cache gradually to avoid file descriptor limits Variables to adjust: table_cache (> 64) innodb_buffer_pool_size (>= 967M) UPDATE 1: When testing the queries listed here there is usually no more than one other query taking place, and usually none. Because production is actually handling apache requests that development gets very few of as it's only myself and 1 other who accesses it - could the 4GB of RAM be getting exhausted by using the single machine for both apache and mysql server? Production: sudo hdparm -tT /dev/sda /dev/sda: Timing cached reads: 24872 MB in 2.00 seconds = 12450.72 MB/sec Timing buffered disk reads: 368 MB in 3.00 seconds = 122.49 MB/sec sudo hdparm -tT /dev/sdb /dev/sdb: Timing cached reads: 24786 MB in 2.00 seconds = 12407.22 MB/sec Timing buffered disk reads: 350 MB in 3.00 seconds = 116.53 MB/sec Server version(mysql + ubuntu versions): 5.1.61-0ubuntu0.10.04.1 Development: sudo hdparm -tT /dev/sda /dev/sda: Timing cached reads: 10632 MB in 2.00 seconds = 5319.40 MB/sec Timing buffered disk reads: 400 MB in 3.01 seconds = 132.85 MB/sec Server version(mysql + ubuntu versions): 5.1.62-0ubuntu0.11.10.1 ORIGINAL DATA : This query is NOT the query in question but is related so ill post it. SELECT f.form_question_has_answer_id FROM form_question_has_answer f INNER JOIN project_company_has_user p ON f.form_question_has_answer_user_id = p.project_company_has_user_user_id INNER JOIN company c ON p.project_company_has_user_company_id = c.company_id INNER JOIN project p2 ON p.project_company_has_user_project_id = p2.project_id INNER JOIN user u ON p.project_company_has_user_user_id = u.user_id INNER JOIN form f2 ON p.project_company_has_user_project_id = f2.form_project_id WHERE (f2.form_template_name = 'custom' AND p.project_company_has_user_garbage_collection = 0 AND p.project_company_has_user_project_id = '29') AND (LCASE(c.company_country) LIKE '%ge%' OR LCASE(c.company_country) LIKE '%abcde%') AND f.form_question_has_answer_form_id = '174' And the explain plan for the above query is, run on both dev and production produce the same plan. +----+-------------+-------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+-------------+ | 1 | SIMPLE | p2 | const | PRIMARY | PRIMARY | 4 | const | 1 | Using index | | 1 | SIMPLE | f | ref | form_question_has_answer_form_id,form_question_has_answer_user_id | form_question_has_answer_form_id | 4 | const | 796 | Using where | | 1 | SIMPLE | u | eq_ref | PRIMARY | PRIMARY | 4 | new_klarents.f.form_question_has_answer_user_id | 1 | Using index | | 1 | SIMPLE | p | ref | project_company_has_user_unique_key,project_company_has_user_user_id,project_company_has_user_company_id,project_company_has_user_project_id | project_company_has_user_user_id | 4 | new_klarents.f.form_question_has_answer_user_id | 1 | Using where | | 1 | SIMPLE | f2 | ref | form_project_id | form_project_id | 4 | const | 15 | Using where | | 1 | SIMPLE | c | eq_ref | PRIMARY | PRIMARY | 4 | new_klarents.p.project_company_has_user_company_id | 1 | Using where | +----+-------------+-------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+-------------+ This query takes 2 minutes ~20 seconds to execute. The query that is ACTUALLY being run on the server is this one: SELECT COUNT(*) AS num_results FROM (SELECT f.form_question_has_answer_id FROM form_question_has_answer f INNER JOIN project_company_has_user p ON f.form_question_has_answer_user_id = p.project_company_has_user_user_id INNER JOIN company c ON p.project_company_has_user_company_id = c.company_id INNER JOIN project p2 ON p.project_company_has_user_project_id = p2.project_id INNER JOIN user u ON p.project_company_has_user_user_id = u.user_id INNER JOIN form f2 ON p.project_company_has_user_project_id = f2.form_project_id WHERE (f2.form_template_name = 'custom' AND p.project_company_has_user_garbage_collection = 0 AND p.project_company_has_user_project_id = '29') AND (LCASE(c.company_country) LIKE '%ge%' OR LCASE(c.company_country) LIKE '%abcde%') AND f.form_question_has_answer_form_id = '174' GROUP BY f.form_question_has_answer_id;) dctrn_count_query; With explain plans (again same on dev and production): +----+-------------+-------+--------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+--------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+------------------------------+ | 1 | PRIMARY | NULL | NULL | NULL | NULL | NULL | NULL | NULL | Select tables optimized away | | 2 | DERIVED | p2 | const | PRIMARY | PRIMARY | 4 | | 1 | Using index | | 2 | DERIVED | f | ref | form_question_has_answer_form_id,form_question_has_answer_user_id | form_question_has_answer_form_id | 4 | | 797 | Using where | | 2 | DERIVED | p | ref | project_company_has_user_unique_key,project_company_has_user_user_id,project_company_has_user_company_id,project_company_has_user_project_id,project_company_has_user_garbage_collection | project_company_has_user_user_id | 4 | new_klarents.f.form_question_has_answer_user_id | 1 | Using where | | 2 | DERIVED | f2 | ref | form_project_id | form_project_id | 4 | | 15 | Using where | | 2 | DERIVED | c | eq_ref | PRIMARY | PRIMARY | 4 | new_klarents.p.project_company_has_user_company_id | 1 | Using where | | 2 | DERIVED | u | eq_ref | PRIMARY | PRIMARY | 4 | new_klarents.p.project_company_has_user_user_id | 1 | Using where; Using index | +----+-------------+-------+--------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+------------------------------+ On the production server the information I have is as follows. Upon execution: +-------------+ | num_results | +-------------+ | 3 | +-------------+ 1 row in set (2 min 14.28 sec) Show profile: +--------------------------------+------------+ | Status | Duration | +--------------------------------+------------+ | starting | 0.000016 | | checking query cache for query | 0.000057 | | Opening tables | 0.004388 | | System lock | 0.000003 | | Table lock | 0.000036 | | init | 0.000030 | | optimizing | 0.000016 | | statistics | 0.000111 | | preparing | 0.000022 | | executing | 0.000004 | | Sorting result | 0.000002 | | Sending data | 136.213836 | | end | 0.000007 | | query end | 0.000002 | | freeing items | 0.004273 | | storing result in query cache | 0.000010 | | logging slow query | 0.000001 | | logging slow query | 0.000002 | | cleaning up | 0.000002 | +--------------------------------+------------+ On development the results are as follows. +-------------+ | num_results | +-------------+ | 3 | +-------------+ 1 row in set (0.08 sec) Again the profile for this query: +--------------------------------+----------+ | Status | Duration | +--------------------------------+----------+ | starting | 0.000022 | | checking query cache for query | 0.000148 | | Opening tables | 0.000025 | | System lock | 0.000008 | | Table lock | 0.000101 | | optimizing | 0.000035 | | statistics | 0.001019 | | preparing | 0.000047 | | executing | 0.000008 | | Sorting result | 0.000005 | | Sending data | 0.086565 | | init | 0.000015 | | optimizing | 0.000006 | | executing | 0.000020 | | end | 0.000004 | | query end | 0.000004 | | freeing items | 0.000028 | | storing result in query cache | 0.000005 | | removing tmp table | 0.000008 | | closing tables | 0.000008 | | logging slow query | 0.000002 | | cleaning up | 0.000005 | +--------------------------------+----------+ If i remove user and/or project innerjoins the query is reduced to 30s. Last bit of information I have: Mysqlserver and Apache are on the same box, there is only one box for production. Production output from top: before & after. top - 15:43:25 up 78 days, 12:11, 4 users, load average: 1.42, 0.99, 0.78 Tasks: 162 total, 2 running, 160 sleeping, 0 stopped, 0 zombie Cpu(s): 0.1%us, 50.4%sy, 0.0%ni, 49.5%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 4037868k total, 3772580k used, 265288k free, 243704k buffers Swap: 3905528k total, 265384k used, 3640144k free, 1207944k cached top - 15:44:31 up 78 days, 12:13, 4 users, load average: 1.94, 1.23, 0.87 Tasks: 160 total, 2 running, 157 sleeping, 0 stopped, 1 zombie Cpu(s): 0.2%us, 50.6%sy, 0.0%ni, 49.3%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 4037868k total, 3834300k used, 203568k free, 243736k buffers Swap: 3905528k total, 265384k used, 3640144k free, 1207804k cached But this isn't a good representation of production's normal status so here is a grab of it from today outside of executing the queries. top - 11:04:58 up 79 days, 7:33, 4 users, load average: 0.39, 0.58, 0.76 Tasks: 156 total, 1 running, 155 sleeping, 0 stopped, 0 zombie Cpu(s): 3.3%us, 2.8%sy, 0.0%ni, 93.9%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 4037868k total, 3676136k used, 361732k free, 271480k buffers Swap: 3905528k total, 268736k used, 3636792k free, 1063432k cached Development: This one doesn't change during or after. top - 15:47:07 up 110 days, 22:11, 7 users, load average: 0.17, 0.07, 0.06 Tasks: 210 total, 2 running, 208 sleeping, 0 stopped, 0 zombie Cpu(s): 0.1%us, 0.2%sy, 0.0%ni, 99.7%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 4111972k total, 1821100k used, 2290872k free, 238860k buffers Swap: 4183036k total, 66472k used, 4116564k free, 921072k cached

    Read the article

  • Syntax error in INSERT INTO statement

    - by user454563
    I wrote a program that connects to MS Access. When I fill in the fields and add a new item to Access the program fails. The exception is "Syntax error in INSERT INTO statement" Here is the relevant code. **************************************************************** AdoHelper.cs **************************************************************** using System; using System.Collections.Generic; using System.Text; using System.Data; using System.Data.OleDb; namespace Yad2 { class AdoHelper { //get the connection string from the app.config file //Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\Yad2.accdb static string connectionString = Properties.Settings.Default.DBConnection.ToString(); //declare the db connection static OleDbConnection con = new OleDbConnection(connectionString); /// <summary> /// To Execute queries which returns result set (table / relation) /// </summary> /// <param name="query">the query string</param> /// <returns></returns> public static DataTable ExecuteDataTable(string query) { try { con.Open(); OleDbCommand command = new OleDbCommand(query, con); System.Data.OleDb.OleDbDataAdapter tableAdapter = new System.Data.OleDb.OleDbDataAdapter(command); DataTable dt = new DataTable(); tableAdapter.Fill(dt); return dt; } catch (Exception ex) { throw ex; } finally { con.Close(); } } /// <summary> /// To Execute update / insert / delete queries /// </summary> /// <param name="query">the query string</param> public static void ExecuteNonQuery(string query) { try { con.Open(); System.Data.OleDb.OleDbCommand command = new System.Data.OleDb.OleDbCommand(query, con); command.ExecuteNonQuery(); } catch (Exception ex) { throw ex; } finally { con.Close(); } } /// <summary> /// To Execute queries which return scalar value /// </summary> /// <param name="query">the query string</param> public static object ExecuteScalar(string query) { try { con.Open(); System.Data.OleDb.OleDbCommand command = new System.Data.OleDb.OleDbCommand(query, con); /// here is the Excaption !!!!!!!!! return command.ExecuteScalar(); } catch { throw; } finally { con.Close(); } } } } **************************************************************************** **************************************************************************** DataQueries.cs **************************************************************************** using System; using System.Collections.Generic; using System.Text; using System.Data; namespace Yad2 { class DataQueries { public static DataTable GetAllItems() { try { string query = "Select * from Messages"; DataTable dt = AdoHelper.ExecuteDataTable(query); return dt; } catch (Exception ex) { throw ex; } } public static void AddNewItem(string mesNumber, string title , string mesDate , string contactMail , string mesType , string Details ) { string query = "Insert into Messages values(" + mesNumber + " , '" + title + "' , '" + mesDate + "' , '" + contactMail + "' , , '" + mesType + "' , '" + Details + "')"; AdoHelper.ExecuteNonQuery(query); } public static void DeleteDept(int mesNumber) { string query = "Delete from Item where MessageNumber=" + mesNumber; AdoHelper.ExecuteNonQuery(query); } } } *********************************************************************************************** plase help me .... why the program falls ?

    Read the article

  • OSLO, ANTLR or other parser grammar, for parsing QUERY EXPRESSION

    - by Jay Allard
    Greetings I'm working on a project that requires me to write queries in text form, then convert them to some easily processed nodes to be processed by some abiguous repository. Of everything there, the part I'm least interested is the part that converts the text to nodes. I'm hoping it's already done somewhere. Because I'm making stuff up as I go, I chose to use a LINQish expression syntax. from m in Movie select m.A, m.B I started parsing it manually and got the basics, but it's pretty cheesy. I'm looking for the better solution. I made some progress using MGrammar, but it would be nice if such a thing already existed. Does anyone know of anything that already does this? I looked for existing ANTLR templates, but no luck. Thanks for the help.

    Read the article

  • How do I get a linq to sql group by query into the asp.net mvc view?

    - by Brad Wetli
    Sorry for the newbie question, but I have the following query that groups parking spaces by their garage, but I can't figure out how to iterate the data in the view. I guess I should strongly type the view but am a newbie and having lots of problems figuring this out. Any help would be appreciated. Public Function FindAllSpaces() Implements ISpaceRepository.FindAllSpaces Dim query = _ From s In db.spaces _ Order By s.name Ascending _ Group By s.garageid Into spaces = Group _ Order By garageid Ascending Return query End Function The controller is taking the query object as is and putting it into the viewdata.model and as stated the view is not currently strongly typed as I haven't been able to figure out how to do this. I have run the query successfully in linqpad.

    Read the article

  • Why won't this sql update query work?

    - by Wesley
    I have a table that has 5,000(table1) lines in it. Currently, 3,000 of them are filled up with data. The remaining values are currently null. In a separate table(table2), I have the remaining 2,000 rows of data. I am simply trying to take the values in table2 and put them in table1, but this statement isn't working: Update table1 Set field1 = (Select field1 From table2 Where table1.id = table2.id) Where Exists(Select field1 From table2 Where table1.id = table2.id) It looks like this should be working, but I am getting an error from Base, the db program I am using that just says error Near " ": syntax error...any help?? Thanks!

    Read the article

  • MySQL Query Cache

    - by BRADINO
    According to MySQL.com the query cache stores the text of a SELECT statement together with the corresponding result that was sent to the client. If an identical statement is received later, the server retrieves the results from the query cache rather than parsing and executing the statement again. The query cache is shared among sessions, so a result set generated by one client can be sent in response to the same query issued by another client. Purely hypothetical example: SELECT `name` FROM `beers` WHERE `favorite` = true To force the database NOT to give you a cached result simply add SQL_NO_CACHE to the query: SELECT SQL_NO_CACHE `name` FROM `beers` WHERE `favorite` = true mysql query cache sql no cache mysql nocache

    Read the article

  • Quickly, syntax error: media_grid.show()

    - by Alex
    i run the app and get this error. the little arrow points to the 'd', dont know what that means. plus i had the same error just before but on this line: from quickly.widgets.dictionary grid import DictionaryGrid the arrow pointed to the 'd' in grid as well. then i changed it to this: from quickly.widgets.dictionary_grid import DictionaryGrid i added a '_' in the middle. and now i have the syntax error in the question. Thanks for any help that is given! Traceback (most recent call last): File "bin/simple-player", line 32, in <module> import simple_player File "/home/alex/simple-player/simple_player/__init__.py", line 14, in <module> from simple_player import SimplePlayerWindow File "/home/alex/simple-player/simple_player/SimplePlayerWindow.py", line 51 media_grid.show() ^ SyntaxError: invalid syntax

    Read the article

  • Do you play Sudoku ?

    - by Gilles Haro
    Did you know that 11gR2 database could solve a Sudoku puzzle with a single query and, most of the time, and this in less than a second ? The following query shows you how ! Simply pass a flattened Sudoku grid to it a get the result instantaneously ! col "Solution" format a9 col "Problem" format a9 with Iteration( initialSudoku, Step, EmptyPosition ) as ( select initialSudoku, InitialSudoku, instr( InitialSudoku, '-' )        from ( select '--64----2--7-35--1--58-----27---3--4---------4--2---96-----27--7--58-6--3----18--' InitialSudoku from dual )    union all    select initialSudoku        , substr( Step, 1, EmptyPosition - 1 ) || OneDigit || substr( Step, EmptyPosition + 1 )         , instr( Step, '-', EmptyPosition + 1 )      from Iteration         , ( select to_char( rownum ) OneDigit from dual connect by rownum <= 9 ) OneDigit     where EmptyPosition > 0       and not exists          ( select null              from ( select rownum IsPossible from dual connect by rownum <= 9 )             where OneDigit = substr( Step, trunc( ( EmptyPosition - 1 ) / 9 ) * 9 + IsPossible, 1 )   -- One line must contain the 1-9 digits                or OneDigit = substr( Step, mod( EmptyPosition - 1, 9 ) - 8 + IsPossible * 9, 1 )      -- One row must contain the 1-9 digits                or OneDigit = substr( Step, mod( trunc( ( EmptyPosition - 1 ) / 3 ), 3 ) * 3           -- One square must contain the 1-9 digits                            + trunc( ( EmptyPosition - 1 ) / 27 ) * 27 + IsPossible                            + trunc( ( IsPossible - 1 ) / 3 ) * 6 , 1 )          ) ) select initialSudoku "Problem", Step "Solution"    from Iteration  where EmptyPosition = 0 ;   The Magic thing behind this is called Recursive Subquery Factoring. The Oracle documentation gives the following definition: If a subquery_factoring_clause refers to its own query_name in the subquery that defines it, then the subquery_factoring_clause is said to be recursive. A recursive subquery_factoring_clause must contain two query blocks: the first is the anchor member and the second is the recursive member. The anchor member must appear before the recursive member, and it cannot reference query_name. The anchor member can be composed of one or more query blocks combined by the set operators: UNION ALL, UNION, INTERSECT or MINUS. The recursive member must follow the anchor member and must reference query_name exactly once. You must combine the recursive member with the anchor member using the UNION ALL set operator. This new feature is a replacement of this old Hierarchical Query feature that exists in Oracle since the days of Aladdin (well, at least, release 2 of the database in 1977). Everyone remembers the old syntax : select empno, ename, job, mgr, level      from   emp      start with mgr is null      connect by prior empno = mgr; that could/should be rewritten (but not as often as it should) as withT_Emp (empno, name, level) as        ( select empno, ename, job, mgr, level             from   emp             start with mgr is null             connect by prior empno = mgr        ) select * from   T_Emp; which uses the "with" syntax, whose main advantage is to clarify the readability of the query. Although very efficient, this syntax had the disadvantage of being a Non-Ansi Sql Syntax. Ansi-Sql version of Hierarchical Query is called Recursive Subquery Factoring. As of 11gR2, Oracle got compliant with Ansi Sql and introduced Recursive Subquery Factoring. It is basically an extension of the "With" clause that enables recursion. Now, the new syntax for the query would be with T_Emp (empno, name, job, mgr, hierlevel) as       ( select E.empno, E.ename, E.job, E.mgr, 1 from emp E where E.mgr is null         union all         select E.empno, E.ename, E.job, E.mgr, T.hierlevel + 1from emp E                                                                                                            join T_Emp T on ( E.mgr = T.empno ) ) select * from   T_Emp; The anchor member is a replacement for the "start with" The recursive member is processed through iterations. It joins the Source table (EMP) with the result from the Recursive Query itself (T_Emp) Each iteration works with the results of all its preceding iterations.     Iteration 1 works on the results of the first query     Iteration 2 works on the results of Iteration 1 and first query     Iteration 3 works on the results of Iteration 1, Iteration 2 and first query. So, knowing that, the Sudoku query it self-explaining; The anchor member contains the "Problem" : The Initial Sudoku and the Position of the first "hole" in the grid. The recursive member tries to replace the considered hole with any of the 9 digit that would satisfy the 3 rules of sudoku Recursion progress through the grid until it is complete.   Another example :  Fibonaccy Numbers :  un = (un-1) + (un-2) with Fib (u1, u2, depth) as   (select 1, 1, 1 from dual    union all    select u1+u2, u1, depth+1 from Fib where depth<10) select u1 from Fib; Conclusion Oracle brings here a new feature (which, to be honest, already existed on other concurrent systems) and extends the power of the database to new boundaries. It’s now up to developers to try and test it and find more useful application than solving puzzles… But still, solving a Sudoku in less time it takes to say it remains impressive… Interesting links: You might be interested by the following links which cover different aspects of this feature Oracle Documentation Lucas Jellema 's Blog Fibonaci Numbers

    Read the article

  • SQL Query Builder/Designer and code Formating

    - by DavRob60
    I write SQL query every now and then, I could easily write them freehand, but sometimes I do create SQL queries using SQL Query Designers for various reason. (I wont start to enumerate them here and/or argue about their usefulness, so let's just say they are sometime useful.) Anyway, I currently use 2 Query Designers : SQL server management studio's Query Designer. Visual Studio 2010's Query Builder (must often within the Table adapter Query Configuration Wizard.) There's something I hate about those two (I don't know about the others), it's the way they throw away my Code formatting of SQL queries after an edit. Is there any way to configure something to automatically reformat the SQL output or is there any external tool/plug-in that I could use to do that job?

    Read the article

  • Alternative of SortedDictionary in Silverlight

    - by Rajneesh Verma
    Hi, As we know SortedDictionary is not not present in Silverlightso to find alternative of this i am using Dictionary as System.Collections.Generic . Dictionary (Of TKey, TValue ) . KeyCollection and for sorting i am using LINQ query. see the full code below. Dim sortedLists As New Dictionary(Of String, Object) Dim query = From sortedList In sortedLists Order By sortedList.Key Ascending Select sortedList.Key, sortedList.Value For Each que In query 'get the key value using que.Key 'get the value using...(read more)

    Read the article

  • Developing instincts and "subconscious debugging" [closed]

    - by ggambett
    For some time now (a couple of years, perhaps?) I've noticed something that happens when I'm writing code. I write something with a syntax error, or some other subtle error. I don't really notice it on a conscious level, but I have a weird feeling about what I just wrote. I then try to compile it and I get a warning or error on the line that provoked the feeling. Lately I've been trying to pay attention to these feelings as they happen, and more often than not, I find errors right there. It's like I'm developing a subconscious debugger (or at least subconscious syntax checking ;)) I've heard of people fixing bugs in their sleep (I did a couple of times), but I don't think I've heard this kind of thing. Does it happen to someone else?

    Read the article

  • query in codeIgniter style

    - by troy
    I have below query: SET @sql = NULL ; SELECT GROUP_CONCAT( DISTINCT CONCAT( 'select latitude,longitude,max(serverTime) as serverTime,', deviceID, ' AS device from d', deviceID, '_gps' ) SEPARATOR ' UNION ALL ' ) INTO @sql FROM devices WHERE accountID =2; PREPARE stmt FROM @sql ; EXECUTE stmt; Can someone help me to write the above query in codeIgniter style.... ANd another thing is :What is the difference between writing the query in 1 and 2 formats 1. $query = $this->db->query('YOUR QUERY HERE'); 2. $this->db->select("..."); $this->db->from(); $this->db->where(); Will it have any effect on performance if we use 2nd style... Thank You

    Read the article

  • Updating query results

    - by Francisco Garcia
    Within a DDD and CQRS context, a query result is displayed as table rows. Whenever new rows are inserted or deleted, their positions must be calculated by comparing the previous query result with the most recent one. This is needed to visualize with an animation new or deleted rows. The model of my view contains an array of the displayed query results. But I need a place to compare its contents against the latest query. Right now I consider my model view part of my application layer, but the comparison of two query result sets seems something that must be done within the domain layer. Which component should cache a query result and which one compare them? Are view models (and their cached contents) supposed to be in the application layer?

    Read the article

  • Online Syntax Colorizer

    - by lavanyadeepak
    Online Syntax Colorizer For those of us who share code snippets along with articles the most daunting problem would be to preserve the syntax colorizations. There are a few ways to manage through this additional requirements: Tweak and point the color picker in the article textearea. Import the code to a word processor and then copy the code. However, the word processor would unnecessarily swell the contents with too much of formatting contents. Quick Online Colorizer: http://tohtml.com/ (This supports a lot of languages including autodetection). I would also recommend if GWB could link to this website and auto-colorize the code when we paste it in our articles.

    Read the article

< Previous Page | 92 93 94 95 96 97 98 99 100 101 102 103  | Next Page >