Search Results

Search found 36756 results on 1471 pages for 'mysql real query'.

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

Page 268/1471 | < Previous Page | 264 265 266 267 268 269 270 271 272 273 274 275  | Next Page >

  • Why would using a Temp table be faster than a nested query?

    - by Mongus Pong
    We are trying to optimise some of our queries. One query is doing the following: SELECT t.TaskID, t.Name as Task, '' as Tracker, t.ClientID, (<complex subquery>) Date, INTO [#Gadget] FROM task t SELECT TOP 500 TaskID, Task, Tracker, ClientID, dbo.GetClientDisplayName(ClientID) as Client FROM [#Gadget] order by CASE WHEN Date IS NULL THEN 1 ELSE 0 END , Date ASC DROP TABLE [#Gadget] (I have removed the complex subquery, cos I dont think its relevant other than to explain why this query has been done as a two stage process.) Now I would have thought it would be far more efficient to merge this down into a single query using subqueries as : SELECT TOP 500 TaskID, Task, Tracker, ClientID, dbo.GetClientDisplayName(ClientID) FROM ( SELECT t.TaskID, t.Name as Task, '' as Tracker, t.ClientID, (<complex subquery>) Date, FROM task t ) as sub order by CASE WHEN Date IS NULL THEN 1 ELSE 0 END , Date ASC This would give the optimiser better information to work out what was going on and avoid any temporary tables. It should be faster. But it turns out it is a lot slower. 8 seconds vs under 5 seconds. I cant work out why this would be the case as all my knowledge of databases imply that subqueries would always be faster than using temporary tables. Can anyone explain what could be going on!?!?

    Read the article

  • Reading data from a MySQL database into a HTML Table?

    - by Michael McKay
    So i am working on a project and need some advice. I have a MySQL database that stores events, i know how to code this functionality in PHP but im just stuck of a few specifics. As the project that I am creating is a timetable, the most important attributes are the day of the event, starting time and finishing time. Once i have read this data from the MYSQL database using my PHP script, how do i go about inserting these events in to a html timetable? Lets say i have record like below in my events table: Event ID = 01 Event Day = Monday Event Start = 12:00 Event End = 14:00 How would I then put that into a html table, bearing in mind that i may have mutiple events for a day?

    Read the article

  • how to compare two tables fields name with another value in mysql?

    - by I Like PHP
    I have two tables table_school school_open_time|school_close_time|school_day 8:00 AM | 9:00PM | Monday 10:00 AM | 7:00PM | Wednesday table_college college_open_time|college_close_time|college_day 10:00 AM | 8:00PM | Monday 10:00 AM | 9:00PM | Tuesday 10:00 AM | 5:00PM | Wednesday Now I want to select school_open_time school_close time, college_open_time and college_close_time according to today (means college_day=school_day=today), and also if there is no row for a specific day in any of one table then it display blank field ( LEFT JOIN , I think I can use). Please suggest me best and optimized query for this. UPDATE: if there is no open time and close time for school then college_open_time and college_close_time has to be returned( not to be filled in database,just return) as school_open_time and school_close_time. and there always must be college_open_time and college_close_time for a given day MORE UPDATE: i m using below query SELECT college_open_time,college_close_time ,school_open_time, school_close_time FROM tbl_college LEFT JOIN tbl_school ON school_owner_id=college_owner_id WHERE college_owner_id='".$_session['user_id']."' AND college_day='".date('l',time())."'"; it return single row (left hand having some value and right hand having blank value) when there is no row of a given day in table_school, BUT display seven rows with same value on left hand side(college_open_time, college_close_time) and 6 blank row on right hand side (school_open_time and school_close_time) i need only one row when both table have a row of a given day but using above query take only first row of corresponding table_school where school_owner_id is 50(let), it not see the condition that school_day name should be given day

    Read the article

  • Best way to have unique key over 500M varchar(255) records in mysql/innodb?

    - by taw
    I have url column with unique key over it - but its performance on updates is absolutely atrocious. I suspect that's because the index doesn't all fit in memory. So I was thinking, how about adding a column of md5(url) with 16 bytes of binary data and unique-keying that instead. What would be the best datatype for that? I'd love to be able to just see 32-character hex hash, while mysql would convert it to/from 16 binary bytes and index that, as programs using the database might have some troubles with arbitrary binary data that I'd rather avoid if possible (also I'm a bit afraid that mysql might get some strange ideas about character sets and for example overalocating storage for that by 3:1 because it thinks it might need utf8, how do I avoid that for cure?).

    Read the article

  • MYSQL - Adding result set A to result set B? Please see my example

    - by BlackberryFan
    I have two mysql tables. They are laid out in this manner: user_info id | emailContact _______________________ 1 | [email protected] 3 | [email protected] user_biz_info id | emailContact _________________________ 8 | [email protected] 9 | [email protected] What kind of join would I use to create a result set of information like this: id | emailContact ________________________________ 1 - [email protected] 3 - [email protected] 8 - [email protected] 9 - [email protected] I have tried the following: SELECT p.id, p.emailContact, b.id, b.emailContact FROM user_info p, user_business_info b But it seems that this is an incorrect approach. Would someone be able to suggest the correct approach in this or possibly point me in the direction of some tutorials that cover this type of mysql join, as this is what I assume is needed in this case. Thanks for your time in reading through my question!!

    Read the article

  • is there a limit of merge tables with Mysql ?

    - by sysko
    I'm working on a database with mysql 5.0 for an open source project it's used to stored sentences in specific languages and their translations in other languages I used to have a big table "sentences" and "sentences_translations" (use to join sentences to sentences) table but has we have now near one million entries, this begin to be a bit slow, moreover, most of request are made using a "where lang =" so I've decided to create a table by language sentences_LANGUAGECODE and sentences_translation_LANGSOURCE_LANGTARGET and to create merge table like this sentences_ENG_OTHERS which merge sentences_ENG_ARA sentences_ENG_DEU etc... when we want to have the translations in all languages of an english sentence sentences_OTHERS_ENG when we want to have only the english translations of some sentences I've created a script to create all these tables (they're around 31 languages so more than 60 merge table), I've tested, that works really great a request which use to take 160ms now take only 30 :) but I discover that all my merge table after the 15th use to have "NULL" as type of storage engine instead of MRG_MYISAM, and if delete one, then I can create an others, using FLUSH table between each creation also allow me to create more merge tables so is this a limitation from mysql ? can we override it ? thanks for your answers

    Read the article

  • Do I need the text "_size" in the my.cnf file for mysql 5.1?

    - by chongman
    This is a pretty simple question about setting parameters in the my.cnf file for mysql 5.1. This page gives me the parameters I can tune: http://dev.mysql.com/doc/refman/5.0/en/server-parameters.html and so I think I would need to write key_buffer_size = 256M But when I open my current my.cnf, it has the line: key_buffer = 16M My question is, do I need "key_buffer_size" or "key_buffer" or does it not matter which I use? And, how would I know if something in the my.cnf is incorrect? Where's the daemon start log file? I am running ubuntu; I think version 8.04 LTS

    Read the article

  • Can MySQL automatically specify `_utf8` for inserts to UTF-8 columns?

    - by Neil
    I have a table like this, where one column is latin1, the other is UTF-8: Create Table: CREATE TABLE `names` ( `name_english` varchar(255) character NOT NULL, `name_chinese` varchar(255) character set utf8 default NULL, ) ENGINE=MyISAM DEFAULT CHARSET=latin1 When I do an insert, I have to type _utf8 before values being inserted into UTF-8 columns: insert into names (name_english = "hooey", name_chinese = _utf8 "??"); However, since MySQL should know that name_chinese is a UTF-8 column, it should be able to know to use _utf8 automatically. Is there any way to tell MySQL to use _utf8 automatically, so when I'm programatically making prepared statements, I don't have to worry about including it with the right parameters?

    Read the article

  • How should I solve this MySql problem (PHP) ? (Beginner)

    - by Camran
    I have several tables in a MySql database. I have a classifieds website, and at the bottom I display the users last visited classifieds. I do this by storing the ID:s of the ads to an array in the cookie. Now, my db is made up like this kindof: Main Table: // Stores global information, ie these fields have to be filled out in every record, never be blank ID Price category Seller Item Table: // Stores descriptive info about whats for sale ID AD_ID (FK) //This is the same as ID in the MAIN TABLE Color Size Mileage etc My problem is that I need to know what category the ad is in, in order to query mysql for the right information I think. So I need two variables, but the cookie only has one (ID) stored. Offcourse I could make two queries, first one just matching the ID to the main_table and fetch the category from the Main_table. Then make the second query and fetch all other info from the right table. Here is an example if the category was Vehicles: SELECT * FROM main_table, vehicles_table, WHERE main_table.id=$id_from_cookie AND main_table.ad_id=vehicles_table.ad_id As you can see above, I need the category to write in what table to check, right? But I think there must be a smarter way, like fetching them in one single query using only one variable (id from cookie)? How should I do this? Understand? Let me know if you need more input... Thanks

    Read the article

  • How to insert large files in mysql database using php? [closed]

    - by anjan
    Hi! I want to upload a large file of size 10M max to my mysql database. Using .htaccess i changed the PHP's own file upload limit to "10485760" = 10M, i am able to upload files upto 10M size without any problem. But i can not insert the file in database if it is more that 1M in size. i am using file_get_contents to read all file data and pass it to the insert query as a string to be inserted into a LONGBLOB field. But files with more than 1M size is not being added to database, though i can use print_r($_FILES) to examine that the file uploaded correctly. Any help will be appreciated and i will need it within next 6 hours. So, please help! best regards, Anjan * This is a duplicate of http://stackoverflow.com/questions/492549/how-can-i-insert-large-files-in-mysql-db-using-php *

    Read the article

  • PHP: reusing database class

    - by citricsquid
    Hi, I built a class that allows me to do: $db->query($query); and it works perfectly, although if I want to do: $db->query($query); while($row = $db->fetch_assoc()){ $db->query($anotherquery); echo $db->result(); } it "breaks" the class. I don't want to constantly have to redeclare my class (eg: $seconddb = new database()), is there a way to get around this? I want to be able to reuse $db within $db, without overwriting the "outside" db. currently I'm create an array of data (from db-fetch_assoc() then doing a foreach and then doing the db call inside that: $db->query('SELECT * FROM table'); while($row = $db->fetch_assoc()){ $arr[] = $row; } foreach($arr as $a){ $db->query(); // query and processing here } Is this the best method or am I missing the obvious? Should I consider passing a connection link ID with the database connection?

    Read the article

  • Which MySQL Datatype to use for storing boolean values from/to PHP?

    - by Beat
    Since MySQL doesn't seem to have any 'boolean' datatype, which datatype do you 'abuse' for storing true/false information in MySQL? Especially in the context of writing and reading from/to a PHP-Script. Over time I have used and seen several approaches: tinyint, varchar fields containing the values 0/1, varchar fields containing the strings '0'/'1' or 'true'/'false' and finally enum Fields containing the two options 'true'/'false'. None of the above seems optimal, I tend to prefer the tinyint 0/1 variant, since automatic type conversion in PHP gives me boolean values rather simply. So which datatype do you use, is there a type designed for boolean values which I have overlooked? Do you see any advantages/disadvantages by using one type or another?

    Read the article

  • You have an error in your SQL syntax; check the manual that corresponds to your MySQL

    - by LuisEValencia
    I am trying to run a mysql query to find all occurences of a text. I have a syntax error but dont know where or how to fix it I am using sqlyog to execute this script DECLARE @url VARCHAR(255) SET @url = '1720' SELECT 'select * from ' + RTRIM(tbl.name) + ' where ' + RTRIM(col.name) + ' like %' + RTRIM(@url) + '%' FROM sysobjects tbl INNER JOIN syscolumns col ON tbl.id = col.id AND col.xtype IN (167, 175, 231, 239) -- (n)char and (n)varchar, there may be others to include AND col.length > 30 -- arbitrary min length into which you might store a URL WHERE tbl.type = 'U' -- user defined table 1 queries executed, 0 success, 1 errors, 0 warnings Query: declare @url varchar(255) set @url = '1720' select 'select * from ' + rtrim(tbl.name) + ' where ' + rtrim(col.name) + ' like %' ... Error Code: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'declare @url varchar(255)

    Read the article

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

< Previous Page | 264 265 266 267 268 269 270 271 272 273 274 275  | Next Page >