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Re: EXISTS operator in SQL ? 10 Years Ago by deceptikon `exists` looks for the first match in the subquery. If it returns true for any of the matches in the outer query, the `where` clause succeeds and that record will be selected. Re: EXISTS operator in SQL ? 10 Years Ago by deceptikon … IN can not be necessarily used as a replacement from Exists, or reverse ? `in` can be used as a replacement… `b` will *always* contain at least one record, and the `exists` test will *always* evaluate to true. Therefore you'll *always… to products that are tied to the customer, and the `exists` works as intended. `in` works in a different manner:… Re: EXISTS operator in SQL ? 10 Years Ago by deceptikon … of those customers to send survey emails. You could use `exists` to retrieve that list and exclude customers that didn't… c.ID, c.Name, c.Email from Customers c where exists (select * from SurveyEnrolement se where se.CustomerID = c.ID); Not… just think it may be a more clear example of `exists`. EXISTS operator in SQL ? 10 Years Ago by HunainHafeez i almost spent 3 hours on EXISTS operation, used in SQL especially with subqueries, i got its … *TABLE GEOGRAPHY* regionName----storeName SELECT SUM(Sales) FROM Store_Information WHERE EXISTS (SELECT * FROM Geography WHERE Region_Name = 'West'); Re: EXISTS operator in SQL ? 10 Years Ago by HunainHafeez but what i concluded is that EXISTS can be handy in situations like IF EXISTS (SELECT ...... from ....... where) Begin DO SOMETHING BECAUSE IT's OBVIOUS THAT TABLE HAS ROWS END correct me if i'm wrong ? Re: EXISTS operator in SQL ? 10 Years Ago by deceptikon … boolean value TRUE, ok ? It will select a matching record. `exists` evaluates to a boolean based on the presence of any… words). I think the issue here may be less about `exists` in particular and more about relational logic in general. Re: EXISTS operator in SQL ? 10 Years Ago by HunainHafeez great replies (Y) so is it correct to say that IN can not be necessarily used as a replacement from Exists, or reverse ? because with IN you can get result set and can match them in WHERE clause but not true for EXISTS since it returns only TRUE OK ? Re: EXISTS operator in SQL ? 10 Years Ago by HunainHafeez … products where prodCategory= 'Consumer electronics') // using Exists Select customers.cus_id, customers.cusName from customers where exists (select cus_id from products where prodCategory… Re: EXISTS operator in SQL ? 10 Years Ago by HunainHafeez let's put it in simple words, the subquery in this code will return on a boolean value TRUE, ok ? where exists (select * from SurveyEnrolement se where se.CustomerID = c.ID); returns true so if it becomes true then it's like a GO signal for Outer query and that get execute ? right ? Re: EXISTS operator in SQL ? 10 Years Ago by JorgeM … test to see if there is a TRUE, meaning record exists. So in deceptikon's example...it will return all records… Re: Need help checking if a file exists 11 Years Ago by yup790 .exists down't work The commented code doesn't work Would it work to write a copy of the exists method in the class Re: Need help checking if a file exists 11 Years Ago by JamesCherrill > .exists down't work .exists does work. It's been in the Java API forever, … file / folder exists 14 Years Ago by darkseid …; " succesfully!", MsgBoxStyle.Information, "Information") ElseIf Directory.Exists(lItem.Text) Then fSource = leftCBselect.Text & lItem.Text Me… folder copy both work but not if add the file.exists / folder.exists lines. if i put a msgbox instead of the… Check if INPUT value Exists 13 Years Ago by jonnypixel …a fadeIN div to say it "already exists" otherwise fadeIN a div to say &… basically if the tag "People" exists in the MYSQL table then i want the …#i2 to fade in and say "Already exists!"[/I][/B][/INDENT] My code is below…strong>Failed:</strong> The keyword already exists.</p> </div> </form… Help with sql query involving not exists 12 Years Ago by cmstoner … w, taggings t WHERE t.taggable_type = 'Workbook' AND NOT EXISTS (SELECT distinct w.name FROM taggings WHERE taggings.taggable_type = 'Workbook…datasources d, taggings t WHERE t.taggable_type = 'Datasource' AND NOT EXISTS (SELECT d.name FROM taggings WHERE taggings.taggable_type = 'Datasource' AND… Checking whether cstudentCode exists 11 Years Ago by prateek29chandra … combobox nd click save button it should check if id exists in table thn only it should update the result. if… two things to be done 1- if id exists or not , 2- if exists it should update it. how can i acheive… as how can i check if student id exists in the above table //if exists update the table, if not thn error Check if a temp table exists and drop the table 10 Years Ago by Nebil … the it,since "the temptable already exists" arises if you want to perform…. "DROP TABLE IF EXISTS LIKE 'prtempTable%'" "DROP TABLE IF EXISTS LIKE '%prtempTable%'" "…;DROP TABLE IF EXISTS WHERE TABLE LIKE 'prtempTable%'"… Python code to check if the file exists within Android Internal Storage 8 Years Ago by Karthik_4 …check whether the **recording** (recordingX.mp3) actually exists with the same name within the specific directory or…>>> print os.path.exists('sdcard/Maverick') False >>> print os.path…; print os.path.exists('sdcard0/Maverick') False >>> print os.path.exists('sdcard0/Maverick/') False… Trying to use List.Exists in C# 16 Years Ago by VernonDozier …> public void AddChild(Node childNode) { if(!this.children.Exists(childNode)) this.children.Add(childNode); } [/code] Line 3… me an error. I am not using [ICODE]Exists[/ICODE] right. The example code I have seen …a boolean function that you pass to the [ICODE]Exists[/ICODE] function, but those functions all have certain … Re: determining if an SQL database exists, etc. 15 Years Ago by mail2saion …CHECK DB EXIST OR NOT: [CODE]if NOT exists(select 1 from master.dbo.sysdatabases where name = …'yourDB') begin print 'DB does not exists'; end[/CODE] Database is accessible: [CODE]Begin Declare… Else Print 'Invalid Database'; End[/CODE] Table Exists/Not: [CODE]IF EXISTS (SELECT * FROM sys.objects WHERE object_id =… Conditional insert using WHERE NOT EXISTS 15 Years Ago by nav33n … ) SELECT name, age, postcode, city FROM b WHERE NOT EXISTS ( SELECT * FROM c WHERE counter = ( SELECT c_id FROM…, postcode, city FROM b where counter = 1 WHERE NOT EXISTS ( SELECT * FROM c WHERE counter = ( SELECT c_id …, postcode, city FROM b where counter = 1) WHERE NOT EXISTS ( SELECT * FROM c WHERE counter = ( SELECT c_id FROM… check dynamically if field exists and add/alter fields to table 15 Years Ago by sunny9977 …to it 1) Check if field already exists and Alter table to add columns/fields …and keep getting error- Field 'notes1' already exists in table 'LUReview'. Item cannot be found…") %> <% '********************** 'Check if form field exists in database table '********************** dbname = "misc.mdb" … Checking if ini Exists 14 Years Ago by Cap'nKirk …is to check if the ini file actually exists on first startup. a snippet of my code…(Application.StartupPath, "SUsettings.ini")); if (ini.Exists()) ini.Load(); else { DialogResult dr = MessageBox.Show(&… does not contain a definition for 'Exists' and no extension method 'Exists' accepting a first argument of type … Re: file / folder exists 14 Years Ago by darkseid … = rightCBselect.Text & lItem.Text If File.Exists(fSource) = True Then My.Computer.FileSystem.MoveFile(fSource…, Me.fTarget) ElseIf Directory.Exists(fSource) = True Then My.Computer.FileSystem.MoveDirectory(fSource… Re: Check if INPUT value Exists 13 Years Ago by jonnypixel …i2').hide(); // this is my div that says tag already exists $("#keyword").click(function() { $('#i1').hide(); // this…$('#i2').hide(); // this is my div that says tag already exists var txt = $.ajax({ url: 'process.php', async: true…strong>Failed:</strong> The keyword already exists. Use Step 2 to add it.</p>… If record exists in MySQL Table then <<Some Code>> 10 Years Ago by henryz_box … record Exist If record Exists then 'User Exists Else 'User does not Exists End If > Even if record Exists cmd.ExecuteScalar() is 0… How To Check Whether An Html Element Or Plain Text Exists On A Page Or Not 7 Years Ago by UI … html element (eg. name=username) or plain text exists or not. If it exists then to give you an alert "TRUE… want it to check if the following text (exact match) exists or not: "I'd like to put forward an… * This is an interesting topic. Base the boolean around what exists or not on a page. Curious to see what the… Re: Trying to use List.Exists in C# 16 Years Ago by selvaganapathy … your own method to search whether the Node is already Exists. Ex [CODE=CSharp] private static bool MyPredicate (Node s) { // Check… true; // else // return false; } [/CODE] Usage [ICODE]if ( !this.children.Exists (MyPredicate) ) this.children.Add(childNode); [/ICODE] Re: Check folder path is exists or not? 15 Years Ago by dinilkarun Dim fso As New FileSystemObject dim Exists as boolean Exists = fso.FolderExists(strFolderName) if exists=True then 'the folder path exists else 'does not exists endif Re: Check if INPUT value Exists 13 Years Ago by hielo …! $('#i2').hide(); // this is my div that says tag already exists $("#keyword").click(function() { $('#i1').hide(); // this is my…! $('#i2').hide(); // this is my div that says tag already exists var txt = $.ajax({ url: 'process.php', async: true, type:'POST…