Search Results

Search found 40581 results on 1624 pages for 'mysql select db'.

Page 207/1624 | < Previous Page | 203 204 205 206 207 208 209 210 211 212 213 214  | Next Page >

  • by jquery, set to option of html-select element selected atribude by text, not value. .

    - by loviji
    hello. I have a select element. <select class='cSelectType'> <option value="1">one</option> <option value="2">two</option> <option value="3">three</option> <option value="4">four</option> <option value="5">five</option> </select> i can by jquery set option value selected like this: $('.cSelectType option[value=4]').attr('selected', 'selected'); And select element will show "Four". By i wont something like this: $('.cSelectType option[xxx=Four]').attr('selected', 'selected'); i.e By text set selected attribute. some ideas please.

    Read the article

  • Get data from MySQL to Android application

    - by Mona
    I want to get data from MySQL database using PHP and display it in Android activity. I code it and pass JSON Array but there is a problem i dont know how to connect to server and my all database is on local server. I code it Kindly tell me where i go wrong so I can get exact results. I'll be very thankful to you. My PHP code is: <?php $response = array(); require_once __DIR__ . '/db_connect.php'; $db = new DB_CONNECT(); if (isset($_GET["cid"])) { $cid = $_GET['cid']; // get a product from products table $result = mysql_query("SELECT *FROM my_task WHERE cid = $cid"); if (!empty($result)) { // check for empty result if (mysql_num_rows($result) > 0) { $result = mysql_fetch_array($result); $task = array(); $task["cid"] = $result["cid"]; $task["cus_name"] = $result["cus_name"]; $task["contact_number"] = $result["contact_number"]; $task["ticket_no"] = $result["ticket_no"]; $task["task_detail"] = $result["task_detail"]; // success $response["success"] = 1; // user node $response["task"] = array(); array_push($response["my_task"], $task); // echoing JSON response echo json_encode($response); } else { // no task found $response["success"] = 0; $response["message"] = "No product found"; // echo no users JSON echo json_encode($response); } } else { // no task found $response["success"] = 0; $response["message"] = "No product found"; echo json_encode($response); } } else { $response["success"] = 0; $response["message"] = "Required field(s) is missing"; // echoing JSON response echo json_encode($response);} ?> My Android code is: public class My_Task extends Activity { TextView cus_name_txt, contact_no_txt, ticket_no_txt, task_detail_txt; EditText attend_by_txtbx, cus_name_txtbx, contact_no_txtbx, ticket_no_txtbx, task_detail_txtbx; Button btnSave; Button btnDelete; String cid; // Progress Dialog private ProgressDialog tDialog; // Creating JSON Parser object JSONParser jParser = new JSONParser(); ArrayList<HashMap<String, String>> my_taskList; // single task url private static final String url_read_mytask = "http://198.168.0.29/mobile/read_My_Task.php"; // url to update product private static final String url_update_mytask = "http://198.168.0.29/mobile/update_mytask.php"; // url to delete product private static final String url_delete_mytask = "http://198.168.0.29/mobile/delete_mytask.php"; // JSON Node names private static String TAG_SUCCESS = "success"; private static String TAG_MYTASK = "my_task"; private static String TAG_CID = "cid"; private static String TAG_NAME = "cus_name"; private static String TAG_CONTACT = "contact_number"; private static String TAG_TICKET = "ticket_no"; private static String TAG_TASKDETAIL = "task_detail"; private static String attend_by_txt; // task JSONArray JSONArray my_task = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_task); cus_name_txt = (TextView) findViewById(R.id.cus_name_txt); contact_no_txt = (TextView)findViewById(R.id.contact_no_txt); ticket_no_txt = (TextView)findViewById(R.id.ticket_no_txt); task_detail_txt = (TextView)findViewById(R.id.task_detail_txt); attend_by_txtbx = (EditText)findViewById(R.id.attend_by_txt); attend_by_txtbx.setText(My_Task.attend_by_txt); Spinner severity = (Spinner) findViewById(R.id.severity_spinner); // Create an ArrayAdapter using the string array and a default spinner layout ArrayAdapter<CharSequence> adapter3 = ArrayAdapter.createFromResource(this, R.array.Severity_array, android.R.layout.simple_dropdown_item_1line); // Specify the layout to use when the list of choices appears adapter3.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); // Apply the adapter to the spinner severity.setAdapter(adapter3); // save button btnSave = (Button) findViewById(R.id.btnSave); btnDelete = (Button) findViewById(R.id.btnDelete); // getting product details from intent Intent i = getIntent(); // getting product id (pid) from intent cid = i.getStringExtra(TAG_CID); // Getting complete product details in background thread new GetProductDetails().execute(); // save button click event btnSave.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View arg0) { // starting background task to update product new SaveProductDetails().execute(); } }); // Delete button click event btnDelete.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View arg0) { // deleting product in background thread new DeleteProduct().execute(); } }); } /** * Background Async Task to Get complete product details * */ class GetProductDetails extends AsyncTask<String, String, String> { /** * Before starting background thread Show Progress Dialog * */ @Override protected void onPreExecute() { super.onPreExecute(); tDialog = new ProgressDialog(My_Task.this); tDialog.setMessage("Loading task details. Please wait..."); tDialog.setIndeterminate(false); tDialog.setCancelable(true); tDialog.show(); } /** * Getting product details in background thread * */ protected String doInBackground(String... params) { // updating UI from Background Thread runOnUiThread(new Runnable() { public void run() { // Check for success tag int success; try { // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("cid", cid)); // getting product details by making HTTP request // Note that product details url will use GET request JSONObject json = JSONParser.makeHttpRequest( url_read_mytask, "GET", params); // check your log for json response Log.d("Single Task Details", json.toString()); // json success tag success = json.getInt(TAG_SUCCESS); if (success == 1) { // successfully received product details JSONArray my_taskObj = json .getJSONArray(TAG_MYTASK); // JSON Array // get first product object from JSON Array JSONObject my_task = my_taskObj.getJSONObject(0); // task with this cid found // Edit Text // display task data in EditText cus_name_txtbx = (EditText) findViewById(R.id.cus_name_txt); cus_name_txtbx.setText(my_task.getString(TAG_NAME)); contact_no_txtbx = (EditText) findViewById(R.id.contact_no_txt); contact_no_txtbx.setText(my_task.getString(TAG_CONTACT)); ticket_no_txtbx = (EditText) findViewById(R.id.ticket_no_txt); ticket_no_txtbx.setText(my_task.getString(TAG_TICKET)); task_detail_txtbx = (EditText) findViewById(R.id.task_detail_txt); task_detail_txtbx.setText(my_task.getString(TAG_TASKDETAIL)); } else { // task with cid not found } } catch (JSONException e) { e.printStackTrace(); } } }); return null; } /** * After completing background task Dismiss the progress dialog * **/ protected void onPostExecute(String file_url) { // dismiss the dialog once got all details tDialog.dismiss(); } } /** * Background Async Task to Save product Details * */ class SaveProductDetails extends AsyncTask<String, String, String> { /** * Before starting background thread Show Progress Dialog * */ @Override protected void onPreExecute() { super.onPreExecute(); tDialog = new ProgressDialog(My_Task.this); tDialog.setMessage("Saving task ..."); tDialog.setIndeterminate(false); tDialog.setCancelable(true); tDialog.show(); } /** * Saving product * */ protected String doInBackground(String... args) { // getting updated data from EditTexts String cus_name = cus_name_txt.getText().toString(); String contact_no = contact_no_txt.getText().toString(); String ticket_no = ticket_no_txt.getText().toString(); String task_detail = task_detail_txt.getText().toString(); // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair(TAG_CID, cid)); params.add(new BasicNameValuePair(TAG_NAME, cus_name)); params.add(new BasicNameValuePair(TAG_CONTACT, contact_no)); params.add(new BasicNameValuePair(TAG_TICKET, ticket_no)); params.add(new BasicNameValuePair(TAG_TASKDETAIL, task_detail)); // sending modified data through http request // Notice that update product url accepts POST method JSONObject json = JSONParser.makeHttpRequest(url_update_mytask, "POST", params); // check json success tag try { int success = json.getInt(TAG_SUCCESS); if (success == 1) { // successfully updated Intent i = getIntent(); // send result code 100 to notify about product update setResult(100, i); finish(); } else { // failed to update product } } catch (JSONException e) { e.printStackTrace(); } return null; } /** * After completing background task Dismiss the progress dialog * **/ protected void onPostExecute(String file_url) { // dismiss the dialog once product uupdated tDialog.dismiss(); } } /***************************************************************** * Background Async Task to Delete Product * */ class DeleteProduct extends AsyncTask<String, String, String> { /** * Before starting background thread Show Progress Dialog * */ @Override protected void onPreExecute() { super.onPreExecute(); tDialog = new ProgressDialog(My_Task.this); tDialog.setMessage("Deleting Product..."); tDialog.setIndeterminate(false); tDialog.setCancelable(true); tDialog.show(); } /** * Deleting product * */ protected String doInBackground(String... args) { // Check for success tag int success; try { // Building Parameters List<NameValuePair> params = new ArrayList<NameValuePair>(); params.add(new BasicNameValuePair("cid", cid)); // getting product details by making HTTP request JSONObject json = JSONParser.makeHttpRequest( url_delete_mytask, "POST", params); // check your log for json response Log.d("Delete Task", json.toString()); // json success tag success = json.getInt(TAG_SUCCESS); if (success == 1) { // product successfully deleted // notify previous activity by sending code 100 Intent i = getIntent(); // send result code 100 to notify about product deletion setResult(100, i); finish(); } } catch (JSONException e) { e.printStackTrace(); } return null; } /** * After completing background task Dismiss the progress dialog * **/ protected void onPostExecute(String file_url) { // dismiss the dialog once product deleted tDialog.dismiss(); } } public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) { // An item was selected. You can retrieve the selected item using // parent.getItemAtPosition(pos) } public void onNothingSelected(AdapterView<?> parent) { // Another interface callback } } My JSONParser code is: public class JSONParser { static InputStream is = null; static JSONObject jObj = null; static String json = ""; // constructor public JSONParser() { } // function get json from url // by making HTTP POST or GET mehtod public static JSONObject makeHttpRequest(String url, String method, List<NameValuePair> params) { // Making HTTP request try { // check for request method if(method == "POST"){ // request method is POST // defaultHttpClient DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); httpPost.setEntity(new UrlEncodedFormEntity(params)); HttpResponse httpResponse = httpClient.execute(httpPost); HttpEntity httpEntity = httpResponse.getEntity(); is = httpEntity.getContent(); }else if(method == "GET"){ // request method is GET DefaultHttpClient httpClient = new DefaultHttpClient(); String paramString = URLEncodedUtils.format(params, "utf-8"); url += "?" + paramString; HttpGet httpGet = new HttpGet(url); HttpResponse httpResponse = httpClient.execute(httpGet); HttpEntity httpEntity = httpResponse.getEntity(); is = httpEntity.getContent(); } } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } try { BufferedReader reader = new BufferedReader(new InputStreamReader( is, "iso-8859-1"), 8); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } is.close(); json = sb.toString(); } catch (Exception e) { Log.e("Buffer Error", "Error converting result " + e.toString()); } // try parse the string to a JSON object try { jObj = new JSONObject(json); } catch (JSONException e) { Log.e("JSON Parser", "Error parsing data " + e.toString()); } // return JSON String return jObj; my all database is in localhost and it is not opening an activity. displays an error "Stopped unexpectedly":( How can i get exact results. Kindly guide me

    Read the article

  • python os.execvp() trying to display mysql tables gives 1049 error - Unknown database error.

    - by Hemanth Murthy
    I have a question related to mysql and python. This command works on the shell, but not when I use os.execvp() $./mysql -D test -e "show tables" +----------------+ | Tables_in_test | +----------------+ | sample | +----------------+ The corresponding piece of code in python would be def execute(): args = [] args.extend(sys.argv[1:]) args.extend([MYSQL, '-D test -e "show tables"']) print args os.execvp(args[0], args) child_pid = os.fork() if child_pid == 0: os.execvp(args[0], args) else: os.wait() The output of this is: [./mysql', '-D test -e "show tables"'] ERROR 1049 (42000): Unknown database ' test -e "show tables"' I am not sure if this is a problem with the python syntax or not. Also, the same command works with os.system() call. os.system(MYSQL + ' -D test -e "show tables"') Please let me know how to get this working. Thanks, Hemanth

    Read the article

  • Erlang Mnesia Equivalent of SQL Select FROM WHERE Field IN (value1, value2, value3, ...)

    - by ErJab
    I have an mnesia table with fields say f1, f2, f3. Now if I were to select all the rows with the field value as V1, I would use mnesia:select and match specifications or a simple mnesia:match_object. Now I need to select all the rows which have V1, V2, V3 ... or Vn (a list of arbitrary length) as the value for field f1. In SQL I would do something like SELECT * FROM tablename WHERE f3 IN (V1, V2, V3, ... , Vn) How do I do this in mnesia?

    Read the article

  • jQuery onchange/onfocus select box to display an image?

    - by SoulieBaby
    Hi all, I need some help finding a jQuery plugin which will allow me to display an image preview from a select list of images - onfocus/onchange.. Example: <select name="image" id="image" class="inputbox" size="1"> <option value=""> - Select Image - </option> <option value="image1.jpg">image1.jpg</option> <option value="image2.jpg">image2.jpg</option> <option value="image3.jpg">image3.jpg</option> </select> <div id="imagePreview"> displays image here </div> Has anyone come across something like this? I've tried searching for it to no avail.. Thank you!

    Read the article

  • Are there any issues with MySQL's i18n(indic language) support ?

    - by anjanb
    Hi All, We're evaluating MySQL and PostgreSQL for building our indic language web application which will use MySQL or PostgreSQL. One of my colleagues mentioned that MySQL had issues with i18n. I mostly come from the Oracle world and although I've played a lil with MySQL, I don't know enough to know that there are issues with its i18n support. Does anyone know issues with MySQL's i18n support and if PostgreSQL would be better placed for building an application with indic language support(kannada, telugu, tamil, etc) ? Just so you know, we're going to be using J2EE to build this application and we will be using JDBC drivers to access the DB. P.S : Will anything change if we were to use Rails to build the app instead of J2EE ? Thank you,

    Read the article

  • How to get #entries of last hour in MySQL, correcting for timezone?

    - by Ferdy
    I am storing activity entries in a MySQL table. The table has a date_created field of type timestamp and through PHP I insert the activity entries based on GMT: $timestamp = gmdate("Y-m-d H:i:s", time()); This works fine. On my client I am on GMT+2. If it is 16:00 here and I insert an entry, it is stored in MySQL as 14:00. This is as expected I guess. My Now I would like to get the number of activity entries from MySQL within the last hour. I'm using the following query: SELECT COUNT(id) as cnt FROM karmalog WHERE user_id = ' 89' AND event='IMG_UPD' AND date_created > DATE_SUB(CURRENT_TIMESTAMP, INTERVAL 1 HOUR) This returns nothing, because CURRENT_TIMESTAMP uses the MySQL timezone settings, which is set to SYSTEM, which is set to GMT+2. I guess what I am looking for is a GMT_CURRENTTIMESTAMP in MySQL, is there such a thing?

    Read the article

  • Dependent Dropdowns with single class element

    - by AJ
    I am trying to create multiple dependent dropdowns (selects) with a unique way. I want to restrict the use of selectors and want to achieve this by using a single class selectors on all SELECTs; by figuring out the SELECT that was changed by its index. Hence, the SELECT[i] that changed will change the SELECT[i+1] only (and not the previous ones like SELECT[i-1]). For html like this: <select class="someclass"> <option value="volvo">Volvo</option> <option value="saab">Saab</option> <option value="mercedes">Mercedes</option> <option value="audi">Audi</option> </select> <select class="someclass"> </select> <select class="someclass"> </select> where the SELECTs other than the first one will get something via AJAX. I see that the following Javascript gives me correct value of the correct SELECT and the value of i also corresponds to the correct SELECT. $(function() { $(".someclass").each(function(i) { $(this).change(function(x) { alert($(this).val() + i); }); }); }); Please note that I really want the minimum selector approach. I just cannot wrap my head around on how to approach this. Should I use Arrays? Like store all the SELECTS in an Array first and then select those? I believe that since the above code already passes the index i, there should be a way without Arrays also. Thanks a bunch. AJ

    Read the article

  • Dependent Dropdowns (Linked Selects) with single class (no other selectors)

    - by AJ
    I am trying to create multiple dependent dropdowns (selects) with a unique way. I want to restrict the use of selectors and want to achieve this by using a single class selectors on all SELECTs; by figuring out the SELECT that was changed by its index. Hence, the SELECT[i] that changed will change the SELECT[i+1] only (and not the previous ones like SELECT[i-1]). For html like this: <select class="someclass"> <option value="volvo">Volvo</option> <option value="saab">Saab</option> <option value="mercedes">Mercedes</option> <option value="audi">Audi</option> </select> <select class="someclass"> </select> <select class="someclass"> </select> where the SELECTs other than the first one will get something via AJAX. I see that the following Javascript gives me correct value of the correct SELECT and the value of i also corresponds to the correct SELECT. $(function() { $(".someclass").each(function(i) { $(this).change(function(x) { alert($(this).val() + i); }); }); }); Please note that I really want the minimum selector approach. I just cannot wrap my head around on how to approach this. Should I use Arrays? Like store all the SELECTS in an Array first and then select those? I believe that since the above code already passes the index i, there should be a way without Arrays also. Thanks a bunch. AJ

    Read the article

  • MySQL Throws NullReferenceException in Finalize... How are you coping with this?

    - by Cyril Gupta
    I am using MySQL with the .Net connector on 64 bit Windows. For some reason Mysql is throwing a NullReferenceException in Finalize. This is the problem here and it seems that its due to a bug described here. This bug was reported in 6.22, but I am getting the issue with 6.23 too so apparently it is not fixed. I am using MySQL both with the helper classes, and by instantiating the connection and the Mysqlcommand object. Does anybody have any idea what part of my code do I need to change to fix this issue? Cause even though this is a bug in Mysql this is not universal because I am not getting the problem in my other projects. MySQL bug report has no details on how to reproduce it either. Any suggestions?

    Read the article

  • when using javascript how do you use select form to do if else statements?

    - by Nelson
    How do you take a value of an option in a select form and use it for a if else statement? for example if apple is selected as an option then write to the document how to make applesauce but orange is selected then write how to make orange? so far I have a basic form and select options and I know how to do the document.write but I dont know how to use a select form with if else thanks for the help

    Read the article

  • how can I get back /usr/local/bin/mysql on Snow Leopard?

    - by Ole Media
    From terminal and trying to uninstall macports, I ran a command, rm -rf / macports...., that erased bunch of stuff. I feel ashamed about this, not realizing the space after /. Since then, mysql is running but I cannot execute any of the mysql commands because it is not under /usr/local/bin/ I went ahead an reinstall mysql but without luck. What steps do you recommend on doing in order to be able to run mysql, mysqlduml, mysqladmin, from terminal? I can access databases from phpmyadmin, so mysql is running, don't ask me how.

    Read the article

  • MySQL: Query to obtain recipes using all given ingredients.

    - by John_A
    hi I have the following simplified tables: CREATE TABLE recipe(id int, name varchar(25)); CREATE TABLE ingredient(name varchar(25)); CREATE TABLE uses_ingredient(recipe_id int, name varchar(25)); I want to make a query that returns all id's of recipes that contain both Chicken and Cream. I have tried SELECT recipe_id FROM uses_ingredient INNER JOIN (SELECT * FROM ingredient WHERE name="Chicken" OR name="Cream") USING (name) GROUP BY recipe_id HAVING COUNT(recipe_id) >= (SELECT COUNT(*) FROM theme); which gives me :"ERROR 1248 (42000): Every derived table must have its own alias" and is probably wrong too. Next I tried SELECT recipe_id FROM (SELECT * FROM ingredient WHERE name="Chicken" OR name="Cream") AS t INNER JOIN uses_ingredient USING (name) GROUP BY recipe_id HAVING COUNT(recipe_id)>= (SELECT COUNT(*) FROM t); which gives "ERROR 1146 (42S02): Table 'recipedb.t' doesn't exist" I want to avoid creating temporary tables including using ENGINE=MEMORY.

    Read the article

  • is NATURAL JOIN any better than SELECT FROM WHERE in terms of performance ?

    - by ashy_32bit
    Today I got into a debate with my project manager about Cartesian products. He says a 'natural join' is somehow much better than using 'select from where' because the later cause the db engine to internally perform a Cartesian product but the former uses another approach that prevents this. As far as I know, the natural join syntax is not any different in anyway than 'select from where' in terms of performance or meaning, I mean you can use either based on your taste. SELECT * FROM table1,table2 WHERE table1.id=table2.id SELECT * FROM table1 NATURAL JOIN table2 please elaborate about the first query causing a Cartesian product but the second one being somehow more smart

    Read the article

  • When using SELECT can you modify the value of a returned field based on other fields?

    - by user570759
    When using MySQL SELECT can you change the value of a returned field based on other fields? For example, if I have this select: SELECT city,state,country FROM table Now if city is empty AND state is empty, I want the value of country to returned empty as well (whether country actually has a value or not). Example table: id | city | state | country ----------------------------- 1 | Here | There | MyCountry 2 | | | YourCountry So with the above table, I want the results for id=1 to return Here,There,MyCountry but the results for id=2 should be empty,empty,empty Thanks

    Read the article

  • Can't install do_mysql gem?

    - by maccy1
    I'm trying to install the do_mysql on my Snow Leopord system Macbook Pro 13", but I keep getting this error: n216-160:~ myself$ sudo gem1.9 install do_mysql Password: Building native extensions. This could take a while... ERROR: Error installing do_mysql: ERROR: Failed to build gem native extension. /opt/local/bin/ruby1.9 extconf.rb checking for mysql_query() in -lmysqlclient... no *** extconf.rb failed *** Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options. Provided configuration options: --with-opt-dir --without-opt-dir --with-opt-include --without-opt-include=${opt-dir}/include --with-opt-lib --without-opt-lib=${opt-dir}/lib --with-make-prog --without-make-prog --srcdir=. --curdir --ruby=/opt/local/bin/ruby1.9 --with-mysql-config --without-mysql-config --with-mysql-dir --without-mysql-dir --with-mysql-include --without-mysql-include=${mysql-dir}/include --with-mysql-lib --without-mysql-lib=${mysql-dir}/lib --with-mysqlclientlib --without-mysqlclientlib Gem files will remain installed in /opt/local/lib/ruby1.9/gems/1.9.1/gems/do_mysql-0.10.0 for inspection. Results logged to /opt/local/lib/ruby1.9/gems/1.9.1/gems/do_mysql-0.10.0/ext/do_mysql_ext/gem_make.out n216-160:~ myself$ I have no idea why. I also reinstalled my verison of MySQL with the MySQL 5.4.3 beta, 64-bit as others suggested but no dice. Does anyone have any idea what is wrong?

    Read the article

  • SQL SERVER – Example of Performance Tuning for Advanced Users with DB Optimizer

    - by Pinal Dave
    Performance tuning is such a subject that everyone wants to master it. In beginning everybody is at a novice level and spend lots of time learning how to master the art of performance tuning. However, as we progress further the tuning of the system keeps on getting very difficult. I have understood in my early career there should be no need of ego in the technology field. There are always better solutions and better ideas out there and we should not resist them. Instead of resisting the change and new wave I personally adopt it. Here is a similar example, as I personally progress to the master level of performance tuning, I face that it is getting harder to come up with optimal solutions. In such scenarios I rely on various tools to teach me how I can do things better. Once I learn about tools, I am often able to come up with better solutions when I face the similar situation next time. A few days ago I had received a query where the user wanted to tune it further to get the maximum out of the performance. I have re-written the similar query with the help of AdventureWorks sample database. SELECT * FROM HumanResources.Employee e INNER JOIN HumanResources.EmployeeDepartmentHistory edh ON e.BusinessEntityID = edh.BusinessEntityID INNER JOIN HumanResources.Shift s ON edh.ShiftID = s.ShiftID; User had similar query to above query was used in very critical report and wanted to get best out of the query. When I looked at the query – here were my initial thoughts Use only column in the select statements as much as you want in the application Let us look at the query pattern and data workload and find out the optimal index for it Before I give further solutions I was told by the user that they need all the columns from all the tables and creating index was not allowed in their system. He can only re-write queries or use hints to further tune this query. Now I was in the constraint box – I believe * was not a great idea but if they wanted all the columns, I believe we can’t do much besides using *. Additionally, if I cannot create a further index, I must come up with some creative way to write this query. I personally do not like to use hints in my application but there are cases when hints work out magically and gives optimal solutions. Finally, I decided to use Embarcadero’s DB Optimizer. It is a fantastic tool and very helpful when it is about performance tuning. I have previously explained how it works over here. First open DBOptimizer and open Tuning Job from File >> New >> Tuning Job. Once you open DBOptimizer Tuning Job follow the various steps indicates in the following diagram. Essentially we will take our original script and will paste that into Step 1: New SQL Text and right after that we will enable Step 2 for Generating Various cases, Step 3 for Detailed Analysis and Step 4 for Executing each generated case. Finally we will click on Analysis in Step 5 which will generate the report detailed analysis in the result pan. The detailed pan looks like. It generates various cases of T-SQL based on the original query. It applies various hints and available hints to the query and generate various execution plans of the query and displays them in the resultant. You can clearly notice that original query had a cost of 0.0841 and logical reads about 607 pages. Whereas various options which are just following it has different execution cost as well logical read. There are few cases where we have higher logical read and there are few cases where as we have very low logical read. If we pay attention the very next row to original query have Merge_Join_Query in description and have lowest execution cost value of 0.044 and have lowest Logical Reads of 29. This row contains the query which is the most optimal re-write of the original query. Let us double click over it. Here is the query: SELECT * FROM HumanResources.Employee e INNER JOIN HumanResources.EmployeeDepartmentHistory edh ON e.BusinessEntityID = edh.BusinessEntityID INNER JOIN HumanResources.Shift s ON edh.ShiftID = s.ShiftID OPTION (MERGE JOIN) If you notice above query have additional hint of Merge Join. With the help of this Merge Join query hint this query is now performing much better than before. The entire process takes less than 60 seconds. Please note that it the join hint Merge Join was optimal for this query but it is not necessary that the same hint will be helpful in all the queries. Additionally, if the workload or data pattern changes the query hint of merge join may be no more optimal join. In that case, we will have to redo the entire exercise once again. This is the reason I do not like to use hints in my queries and I discourage all of my users to use the same. However, if you look at this example, this is a great case where hints are optimizing the performance of the query. It is humanly not possible to test out various query hints and index options with the query to figure out which is the most optimal solution. Sometimes, we need to depend on the efficiency tools like DB Optimizer to guide us the way and select the best option from the suggestion provided. Let me know what you think of this article as well your experience with DB Optimizer. Please leave a comment. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Joins, SQL Optimization, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

    Read the article

  • Highlights from recent Yammer video

    - by Eric Jensen
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} A few weeks back, Ryan Kennedy of Yammer gave a talk about Berkeley DB Java Edition. You can find it posted here on Alex Popescu's Blog, or go directly to the video post itself. It was full of useful nuggets of information, such as why they chose to use BDB JE, performance, and some tips & tricks at the end. At over 40 minutes, the video is quite long. Ryan is an entertaining speaker, so I suggest you watch all of it. But if you only have time for the highlights, here are some times you can sync to:  06:18 hear the Berkeley DB JE features that caused Yammer select it, including: replication auto leader election, failover configurable durability and consistency guarantees 23:10 System performance characteristics 35:08 Check out the tips and tricks for using Berkeley DB JE I know the Berkeley DB development team is very pleased that BDB JE is working out well for Yammer. We definitely encourage others out there to take note of this success, especially if your requirements are similar to Yammer's (which Ryan outlines at the beginning of his talk)

    Read the article

  • how to select all the data from many tables?

    - by Syom
    how to select all the data from many tables? i try `"SELECT * FROM `table1`, `table2`"` , but result none understandable for me. it returns only some rows from table1, and 3 times all the data from table2. i've red one same question here, but don't understand the answer. so could you help me? thanks in advance. update: when i try (SELECT * FROM `videos`) UNION (SELECT * FROM `users`) it returns #1222 - The used SELECT statements have a different number of columns

    Read the article

  • Mysql - innoDb - is in the future! Current system log sequence number

    - by Ward Loockx
    I have this error in my syslog. I restored an older dump to solve this problem, after some reading. Now The errors in syslog are far less than before. But still a few times an hour I get Sep 1 14:23:29 homer mysqld: 120901 14:23:29 InnoDB: Error: page 96637 log sequence number 7 1223357717 Sep 1 14:23:29 homer mysqld: InnoDB: is in the future! Current system log sequence number 6 647303887. Sep 1 14:23:29 homer mysqld: InnoDB: Your database may be corrupt or you may have copied the InnoDB Sep 1 14:23:29 homer mysqld: InnoDB: tablespace but not the InnoDB log files. See Sep 1 14:23:29 homer mysqld: InnoDB: http://dev.mysql.com/doc/refman/5.1/en/forcing-recovery.html Sep 1 14:23:29 homer mysqld: InnoDB: for more information. Sep 1 14:23:29 homer mysqld: 120901 14:23:29 InnoDB: Error: page 96638 log sequence number 8 150027924 Sep 1 14:23:29 homer mysqld: InnoDB: is in the future! Current system log sequence number 6 647303887. Sep 1 14:23:29 homer mysqld: InnoDB: Your database may be corrupt or you may have copied the InnoDB Sep 1 14:23:29 homer mysqld: InnoDB: tablespace but not the InnoDB log files. See Sep 1 14:23:29 homer mysqld: InnoDB: http://dev.mysql.com/doc/refman/5.1/en/forcing-recovery.html Sep 1 14:23:29 homer mysqld: InnoDB: for more information. Sep 1 14:23:29 homer mysqld: 120901 14:23:29 InnoDB: Error: page 96639 log sequence number 7 4208567151 Sep 1 14:23:29 homer mysqld: InnoDB: is in the future! Current system log sequence number 6 647303887. Sep 1 14:23:29 homer mysqld: InnoDB: Your database may be corrupt or you may have copied the InnoDB Sep 1 14:23:29 homer mysqld: InnoDB: tablespace but not the InnoDB log files. See Sep 1 14:23:29 homer mysqld: InnoDB: http://dev.mysql.com/doc/refman/5.1/en/forcing-recovery.html Sep 1 14:23:29 homer mysqld: InnoDB: for more information. Anybody that knows how I can track what database is causing this issue? And how to fix?

    Read the article

  • What method of MySQL mirroring should I use for this?

    - by user45745
    I'm running an web application hosting service (basically hosting forums for free), and I have two remote servers at my disposal. The code for the application is stored on both servers and isn't a problem, but I'm wondering how to deal with the databases. When someone goes onto a site *.example-host.com, they are sent to one of the two servers and both must be capable of loading the forums from a database. The database must also have write access, for when new members register or post topics etc. The main requirement is speed, but uptime is also important (if a server goes out, the site should still work). I have a few options, but I'm inexperienced and not sure which to go with: 1) [PHP] Split the forum records 50:50 between the two servers. If a server does not have the record for a forum requested, it can request it from the other by remote MySQL and load it. This idea sounded okay, until I realised that 50% of the time, users would be waiting significantly longer for pages to load. I also realised that if one of the servers went down, half the forums would be inaccessible and registrations would have to be disabled. 2) [MySQL] Dual master replication. This would attempt to mirror the two databases and sounds perfect, but I've heard that it can be very problematic. I don't know how fast this is. 3) [MySQL] Use a standard replication, distribute read only queries on both nodes and read/write queries to the master. This sounds like a good option, but again, I'm not sure on speed. I also don't know what would happen if the master server went down. If you have any other suggestions, please post them :)

    Read the article

< Previous Page | 203 204 205 206 207 208 209 210 211 212 213 214  | Next Page >