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  • sqlite3 date operations when joining two tables in a view?

    - by duncan
    In short, how to add minutes to a datetime from an integer located in another table, in one select statement, by joining them? I have a table P(int id, ..., int minutes) and a table S(int id, int p_id, datetime start) I want to generate a view that gives me PS(S.id, P.id, S.start + P.minutes) by joining S.p_id=P.id The problem is, if I was generating the query from the application, I can do stuff like: select datetime('2010-04-21 14:00', '+20 minutes'); 2010-04-21 14:20:00 By creating the string '+20 minutes' in the application and then passing it to sqlite. However I can't find a way to create this string in the select itself: select p.*,datetime(s.start_at, formatstring('+%s minutes', p.minutes)) from p,s where s.p_id=p.id; Because sqlite as far the documentation tells, does not provide any string format function, nor can I see any alternative way of expressing the date modifiers.

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  • Get current session /process id from inside a mysql query

    - by Indra Ginanjar
    I'm trying to create a table for pseudo array variable. That looks like CREATE TABLE IF NOT EXISTS `MyArray`.`ArrayTable` ( `ID` INT UNSIGNED NOT NULL COMMENT 'Hash value of SessionID + ArrayName' , `SessionID` INT UNSIGNED NOT NULL , `ArrayName` CHAR(26) NOT NULL COMMENT '32 digit char - 6 digit longest process id (assumtion)' , `Index` INT UNSIGNED NOT NULL , `Value` TEXT NOT NULL , PRIMARY KEY (`ID`, `SessionID`) ) ENGINE = MyISAM; The table is not normalized yet, 'hope this will make it a little simpler to understand :) To avoid collission between client, there should be a differentiator between client session. For that reason i think need to know current session/process id (just like "SHOW PROCESSLIST") but really need to know IN WHICH process the query are?

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  • MySQL, return only rows where there are duplicates among two columns.

    - by Richard Waite
    I have a table in MySQL of contact information ; first name, last name, address, etc. I would like to run a query on this table that will return only rows with first and last name combinations which appear in the table more than once. I do not want to group the "duplicates" (which may only be duplicates of the first and last name, but not other information like address or birthdate) - I want to return all the "duplicate" rows so I can look over the results and determine if they are dupes or not. This seemed like it would be a simple thing to do, but it has not been. Every solution I can find either groups the dupes and gives me a count only (which is not useful for what I need to do with the results) or doesn't work at all. Is this kind of logic even possible in a query ? Should I try and do this in Python or something?

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  • SQL Trigger dont works...

    - by Gabotron
    Is there a way in which a Trigger is not fired? We have this situation: We have a table and there are rows that are been deleted. We need to know who and/or when these row are deleted. We create this trigger: ALTER TRIGGER [dbo].[AUDITdel_nit] ON [dbo].[Client] FOR DELETE AS Insert into AUDIT select 'Delete', getdate(), 'Row Deleted', SYSTEM_USER, host_name(), (select 'ID Client: ' + convert(varchar(12),Id) from deleted), 'Client' ,APP_NAME() We made somte test: deleting rows vis stored procedures and the deleted rows appears in our AUDIT table. But suddenly today we found a row deleted that dont appears in the AUDIT table... Any idea how it can be done?

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  • need to find differences between 2 identically structured sql tables

    - by balalakshmi
    I need to find differences between 2 identically structured sql tables Each table is being uploaded from a 3rd paty tool into sqlserver database. The table structure is: Issue ID-status-Who Issue ID will not repeated within a table, though its not defined explicitly as primary Key There could be additions/deletions/Updations between any 2 tables. What I need Number of rows added & their details Number of rows deleted & their details Number of rows deleted & their details How do I do this 1) is it better to use sql 2) or use datatables

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  • SQL Find duplicate sets

    - by Aheho
    given this Schema: table tblSET SetID int PK SetName nvarchar(100) Table tblSetItem SetID int PK ItemID int PK tblSetItem.SetID is a FK into the tblSet Table. Some data: tblSet SetID SetName 1 Red 2 Blue 3 Maroon 4 Yellow 5 Sky tblSetItem SetID ItemID 1 100 1 101 2 100 2 108 2 109 3 100 3 101 4 101 4 108 4 109 4 110 5 100 5 108 5 109 I'd like a way to identify which sets contain the same items. In the example above Red and Maroon contain the same items (100,101) and Blue and Sky contain the same values (100,108,109) Is there a sql query which would provide this answer?

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  • Awk appears to disconnect my DB2 session when piping

    - by greggannicott
    Hello. I'm attempting to run the following command in Korn Shell (ksh): set -A INDEXES `db2 "describe indexes for table ${TABSCHEMA}.${TABNAME} show detail" | awk '{print $1"."$2}'` What I'm attempting to achieve is place a list of the indexes over a particular table into an array which I can later iterate through. The problem is, when I run the above command the contents of the array starts with the error message of 'SQL1024N' (which is telling me that the database connection does not exist). However, if I remove the 'awk' at the end of the statement as so: set -A INDEXES `db2 "describe indexes for table ${TABSCHEMA}.${TABNAME} show detail"` it works just fine (well, to the extent its returning data. Obviously without the awk I'm not capturing the correct data). Does anyone know why the awk is having this affect? I appreciate there is more than one way to get this data, but it baffles me as to why this is happening. Thanks in advance. Greg.

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  • Turn database result into array

    - by Industrial
    Hi everyone, I have just made the update/add/delete part for the "Closure table" way of organizing query hierarchical data that are shown on page 70 in this slideshare: http://www.slideshare.net/billkarwin/sql-antipatterns-strike-back My database looks like this: Table Categories: ID Name 1 Top value 2 Sub value1 Table CategoryTree: child parent 1 1 2 2 2 1 However, I have a bit of an issue getting the full tree back as an multidimensional array from a single query. Here's what I would like to get back: array ( 'topvalue' = array ( 'Subvalue', 'Subvalue2', 'Subvalue3' = array ('Subvalue 1', 'Subvalue 2', 'Subvalue 3' ) ); ); Update: Found this link, but I still have a hard time to convert it into an array: http://karwin.blogspot.com/2010/03/rendering-trees-with-closure-tables.html

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  • Fastest way to move records from a oracle DB into MS sql server after processing

    - by user347748
    Hi.. Ok this is the scenario...I have a table in Oracle that acts like a queue... A VB.net program reads the queue and calls a stored proc in MS SQL Server that processes and then inserts the message into another SQL server table and then deletes the record from the oracle table. We use a datareader to read the records from Oracle and then call the stored proc for each of the records. The program seems to be a little slow. The stored procedure itself isnt slow. The SP by itself when called in a loop can process about 2000 records in 20 seconds. BUt when called from the .Net program, the execution time is about 5 records per second. I have seen that most of the time consumed is in calling the stored procedure and waiting for it to return. Is there a better way of doing this? Here is a snippet of the actual code Function StartDataXfer() As Boolean Dim status As Boolean = False Try SqlConn.Open() OraConn.Open() c.ErrorLog(Now.ToString & "--Going to Get the messages from oracle", 1) If GetMsgsFromOracle() Then c.ErrorLog(Now.ToString & "--Got messages from oracle", 1) If ProcessMessages() Then c.ErrorLog(Now.ToString & "--Finished Processing all messages in the queue", 0) status = True Else c.ErrorLog(Now.ToString & "--Failed to Process all messages in the queue", 0) status = False End If Else status = True End If StartDataXfer = status Catch ex As Exception Finally SqlConn.Close() OraConn.Close() End Try End Function Private Function GetMsgsFromOracle() As Boolean Try OraDataAdapter = New OleDb.OleDbDataAdapter OraDataTable = New System.Data.DataTable OraSelCmd = New OleDb.OleDbCommand GetMsgsFromOracle = False With OraSelCmd .CommandType = CommandType.Text .Connection = OraConn .CommandText = GetMsgSql End With OraDataAdapter.SelectCommand = OraSelCmd OraDataAdapter.Fill(OraDataTable) If OraDataTable.Rows.Count > 0 Then GetMsgsFromOracle = True End If Catch ex As Exception GetMsgsFromOracle = False End Try End Function Private Function ProcessMessages() As Boolean Try ProcessMessages = False PrepareSQLInsert() PrepOraDel() i = 0 Dim Method As Integer Dim OraDataRow As DataRow c.ErrorLog(Now.ToString & "--Going to call message sending procedure", 2) For Each OraDataRow In OraDataTable.Rows With OraDataRow Method = GetMethod(.Item(0)) SQLInsCmd.Parameters("RelLifeTime").Value = c.RelLifetime SQLInsCmd.Parameters("Param1").Value = Nothing SQLInsCmd.Parameters("ID").Value = GenerateTransactionID() ' Nothing SQLInsCmd.Parameters("UID").Value = Nothing SQLInsCmd.Parameters("Param").Value = Nothing SQLInsCmd.Parameters("Credit").Value = 0 SQLInsCmd.ExecuteNonQuery() 'check the return value If SQLInsCmd.Parameters("ReturnValue").Value = 1 And SQLInsCmd.Parameters("OutPutParam").Value = 0 Then 'success 'delete the input record from the source table once it is logged c.ErrorLog(Now.ToString & "--Moved record successfully", 2) OraDataAdapter.DeleteCommand.Parameters("P(0)").Value = OraDataRow.Item(6) OraDataAdapter.DeleteCommand.ExecuteNonQuery() c.ErrorLog(Now.ToString & "--Deleted record successfully", 2) OraDataAdapter.Update(OraDataTable) c.ErrorLog(Now.ToString & "--Committed record successfully", 2) i = i + 1 Else 'failure c.ErrorLog(Now.ToString & "--Failed to exec: " & c.DestIns & "Status: " & SQLInsCmd.Parameters("OutPutParam").Value & " and TrackId: " & SQLInsCmd.Parameters("TrackID").Value.ToString, 0) End If If File.Exists("stop.txt") Then c.ErrorLog(Now.ToString & "--Stop File Found", 1) 'ProcessMessages = True 'Exit Function Exit For End If End With Next OraDataAdapter.Update(OraDataTable) c.ErrorLog(Now.ToString & "--Updated Oracle Table", 1) c.ErrorLog(Now.ToString & "--Moved " & i & " records from Oracle to SQL Table", 1) ProcessMessages = True Catch ex As Exception ProcessMessages = False c.ErrorLog(Now.ToString & "--MoveMsgsToSQL: " & ex.Message, 0) Finally OraDataTable.Clear() OraDataTable.Dispose() OraDataAdapter.Dispose() OraDelCmd.Dispose() OraDelCmd = Nothing OraSelCmd = Nothing OraDataTable = Nothing OraDataAdapter = Nothing End Try End Function Public Function GenerateTransactionID() As Int64 Dim SeqNo As Int64 Dim qry As String Dim SqlTransCmd As New OleDb.OleDbCommand qry = " select seqno from StoreSeqNo" SqlTransCmd.CommandType = CommandType.Text SqlTransCmd.Connection = SqlConn SqlTransCmd.CommandText = qry SeqNo = SqlTransCmd.ExecuteScalar If SeqNo > 2147483647 Then qry = "update StoreSeqNo set seqno=1" SqlTransCmd.CommandText = qry SqlTransCmd.ExecuteNonQuery() GenerateTransactionID = 1 Else qry = "update StoreSeqNo set seqno=" & SeqNo + 1 SqlTransCmd.CommandText = qry SqlTransCmd.ExecuteNonQuery() GenerateTransactionID = SeqNo End If End Function Private Function PrepareSQLInsert() As Boolean 'function to prepare the insert statement for the insert into the SQL stmt using 'the sql procedure SMSProcessAndDispatch Try Dim dr As DataRow SQLInsCmd = New OleDb.OleDbCommand With SQLInsCmd .CommandType = CommandType.StoredProcedure .Connection = SqlConn .CommandText = SQLInsProc .Parameters.Add("ReturnValue", OleDb.OleDbType.Integer) .Parameters("ReturnValue").Direction = ParameterDirection.ReturnValue .Parameters.Add("OutPutParam", OleDb.OleDbType.Integer) .Parameters("OutPutParam").Direction = ParameterDirection.Output .Parameters.Add("TrackID", OleDb.OleDbType.VarChar, 70) .Parameters.Add("RelLifeTime", OleDb.OleDbType.TinyInt) .Parameters("RelLifeTime").Direction = ParameterDirection.Input .Parameters.Add("Param1", OleDb.OleDbType.VarChar, 160) .Parameters("Param1").Direction = ParameterDirection.Input .Parameters.Add("TransID", OleDb.OleDbType.VarChar, 70) .Parameters("TransID").Direction = ParameterDirection.Input .Parameters.Add("UID", OleDb.OleDbType.VarChar, 20) .Parameters("UID").Direction = ParameterDirection.Input .Parameters.Add("Param", OleDb.OleDbType.VarChar, 160) .Parameters("Param").Direction = ParameterDirection.Input .Parameters.Add("CheckCredit", OleDb.OleDbType.Integer) .Parameters("CheckCredit").Direction = ParameterDirection.Input .Prepare() End With Catch ex As Exception c.ErrorLog(Now.ToString & "--PrepareSQLInsert: " & ex.Message) End Try End Function Private Function PrepOraDel() As Boolean OraDelCmd = New OleDb.OleDbCommand Try PrepOraDel = False With OraDelCmd .CommandType = CommandType.Text .Connection = OraConn .CommandText = DelSrcSQL .Parameters.Add("P(0)", OleDb.OleDbType.VarChar, 160) 'RowID .Parameters("P(0)").Direction = ParameterDirection.Input .Prepare() End With OraDataAdapter.DeleteCommand = OraDelCmd PrepOraDel = True Catch ex As Exception PrepOraDel = False End Try End Function WHat i would like to know is, if there is anyway to speed up this program? Any ideas/suggestions would be highly appreciated... Regardss, Chetan

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  • SQL Function for On Balance Volume (Financial Query)

    - by CraigJSte
    I would like to create a function for On Balance Volume (SQL Function). This is too complex of a calculation for met to figure out but here is the outline of the User Defined Table Function. If someone could help me to fill in the blanks I would appreciate it. Craig CREATE FUNCTION [dbo].[GetStdDev3] (@TKR VARCHAR(10)) RETURNS @results TABLE ( dayno SMALLINT IDENTITY(1,1) PRIMARY KEY , [date] DATETIME , [obv] FLOAT ) AS BEGIN DECLARE @rowcount SMALLINT INSERT @results ([date], [obv]) // CREATE A FUNCTION FOR ON BALANCE VOLUME // On Balance Volume is the Summ of Volume for Total Periods // OBV = 1000 at Period = 0 // OBV = OBV Previous + Previous Volume if Close Previous Close // OBV = OBV Previous - Previous Volume if Close < Previous Close // OBV = OBV Previous if Close = Previous Close // The actual Value of OBV is not important so to keep the ratio low we reduce the // Total Value of Tickers by 1/10th or 1/100th // For Value of Volume = Volume * .01 if Volume < 999 // For Value of Volume = Volume * .001 If Volume = 999 FROM Tickers RETURN END This is the Tickers table [dbo].[Tickers]( [ticker] [varchar](10) NULL, [date] [datetime] NULL, [high] [float] NULL, [low] [float] NULL, [open] [float] NULL, [close] [float] NULL, [volume] [float] NULL, [time] [datetime] NULL, [change] [float] NULL )

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  • MySQL: Limit output according to associated ID

    - by Jess
    So here's my situation. I have a books table and authors table. An author can have many books... In my authors page view, the user (logged in) can click an author in a tabled row and be directed to a page displaying the author's books (collected like this URI format: viewauthorbooks.php?author_id=23), very straight forward... However, in my query, I need to display the books for the author only, and not all books stored in the books table (as i currently have!) As I am a complete novice, I used the most simple query of: SELECT * FROM tasks_tb This returns the books for me, but returns every single value (book) in the database, and not ones associated with the selected author. And when I click a different author the same books are displayed for them...I think everyone gets what I'm trying to achieve, I just don't know how to perform the query. I'm guessing that I need to start using more advanced query clauses like INNER JOIN etc. Anyone care to help me out :)

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  • SQL HAVING COUNT and JOIN

    - by user1833274
    I have tried to this query: What are the doctors that work on less than 2 Hospitals. I have these tables: CREATE TABLE Hospital ( hid INT PRIMARY KEY, name VARCHAR(127) UNIQUE, country VARCHAR(127), area INT ); CREATE TABLE Doctor ( ic INT PRIMARY KEY, name VARCHAR(127), date_of_birth INT, ); CREATE TABLE Work ( hid INT, ic INT, since INT, FOREIGN KEY (hid) REFERENCES Hospital (hid), FOREIGN KEY (ic) REFERENCES Doctor (ic), PRIMARY KEY (hid,ic) ); I tried with this: SELECT DISTINCT D.ic FROM Doctor D, Work W JOIN Hospital H ON (H.hid = W.hid) WHERE D.bi = W.bi GROUP BY (D.ic) HAVING COUNT(H.hid) < 2 ;

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  • The C vs. C++ way

    - by amc
    Hi, So I have to write a program that will iterate through an image and record the pixel locations corresponding to each color pixel that appears in it. For example, given http://www.socuteurl.com/fishywishykissy I need to find the coordinates of all yellow, purple, dark pink, etc pixels. In C++ I would use a hash table to do this. I would iterate through the image, check each pixel's value, look up that value and either add to a vector of pixel coordinates if it were found or add a new entry to the table if the value were not already there. The problem is that I may need to write this program in pure C instead of C++. How would I go about doing this in C? I feel like implementing a hash table would be pretty obnoxious and error-prone: should I avoid doing that? I'm pretty inexperienced with C and have a fair amount of C++ experience, if that matters. Thanks.

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  • sql insert statement with a lot of same where clause and one different where cluase

    - by william
    I m sry if the title is not clear. Here's my proble. I created a new table which will show total, average and maximum values. I have to insert the results into that table. That table will have only 4 rows. No Appointment, Appointment Early, Appointment Late and Appointment Punctual. So.. I have sth like.. insert into newTable select 'No Appointment' as 'Col1', avg statement, total statement, max statement from orgTable where (general conditions) and (unique condition to check NO APPOINTMENT); I have to do that same thing for another 3 rows.. where only the unique condition is different to check early, punctual or late.. So..the statement is super long. I wanna reduce the size.. How can I achieve that?

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  • How to integrate yahoo user interface with cakePHP

    - by ygmehboob
    Hi all I am very new to cakePHP, I want to add YUI accordion in the default layout of my application. A simple explanation could be like this - I have a table 'lecturers' in my database. I have baked the model lecturer (file) I have baked the controller lecturers_controller (file) I have baked the view lecturers (folder) I need to override the default layout but I want to add YUI 3 accordion sothat the table name lecturers will be on top, after clicking on the top division it will slidedown and will show me the column name of lecturer table. Is there anyone who could suggest me how to integrate the YUI 3 accordion - Do I have to write a helper for this or simply after copying the YUI 3 library I could code this in the default.ctp file. I am really confused as I could hardly get a full tutorial on this topic. Thank you in advance ................

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  • Joining two tables (through a link), one which may yield multiple rows, together into one result.

    - by Eikern
    Lets say I've got a table listing car brands or models: Cars: Id | Brand ----------- 1 | BMW 2 | Audi 3 | Volvo And I've also got another table which links features. Link: Id | carid | featureid ----------------------- 1 | 1 | 1 2 | 1 | 2 3 | 2 | 2 4 | 3 | 1 5 | 3 | 2 6 | 3 | 3 And I've got the table listing the features. Features: Id | Feature ----------- 1 | A/C 2 | 4WD 3 | Heated seats I want to list these results on my front page like this: BMW A/C 4WD Audi 4WD Volvo A/C 4WD Heated seats What's the best/most efficient way of doing this (using PHP and MySQL)?

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  • sql combine two subqueries

    - by Claudiu
    I have two tables. Table A has an id column. Table B has an Aid column and a type column. Example data: A: id -- 1 2 B: Aid | type ----+----- 1 | 1 1 | 1 1 | 3 1 | 1 1 | 4 1 | 5 1 | 4 2 | 2 2 | 4 2 | 3 I want to get all the IDs from table A where there is a certain amount of type 1 and type 3 actions. My query looks like this: SELECT id FROM A WHERE (SELECT COUNT(type) FROM B WHERE B.Aid = A.id AND B.type = 1) = 3 AND (SELECT COUNT(type) FROM B WHERE B.Aid = A.id AND B.type = 3) = 1 so on the data above, just the id 1 should be returned. Can I combine the 2 subqueries somehow?

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  • How do I map repeating columns in NHibernate without creating duplicate properties

    - by Ian Oakes
    Given a database that has numerous repeating columns used for auditing and versioning, what is the best way to model it using NHibernate, without having to repeat each of the columns in each of the classes in the domain model? Every table in the database repeats these same nine columns, the names and types are identical and I don't want to replicate it in the domain model. I have read the docs and I saw the section on inheritance mapping but I couldn't see how to make it work in this scenario. This seems like a common scenario because nearly every database I've work on has had the four common audit columns (CreatedBy, CreateDate, UpdatedBy, UpdateDate) in nearly every table. This database is no different except that it introduces another five columns which are common to every table.

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  • Having trouble comparing a range of dates entered in a form with records in a mySQL database

    - by Andrew Fox
    I have a table called schedule and a column called Date where the column type is date. In that column I have a range of dates, which is currently from 2012-11-01 to 2012-11-30. I have a small form where the user can enter a range of dates (input names from and to) and I want to be able to compare the range of dates with the dates currently in the database. This is what I have: //////////////////////////////////////////////////////// //////First set the date range that we want to use////// //////////////////////////////////////////////////////// if(isset($_POST['from']) && ($_POST['from'] != NULL)) { $startDate = $_POST['from']; } else { //Default date is Today $startDate = date("Y-m-d"); } if(isset($_POST['to']) && ($_POST['to'] != NULL)) { $endDate = $_POST['to']; } else { //Default day is one month from today $endDate = date("Y-m-d", strtotime("+1 month")); } ////////////////////////////////////////////////////////////////////////////////////// //////Next calculate the total amount of days selected above to use as a limiter////// ////////////////////////////////////////////////////////////////////////////////////// $dayStart = strtotime($startDate); $dayEnd = strtotime($endDate); $total_days = abs($dayEnd - $dayStart) / 86400 +1; echo "Start Date: " . $startDate . "<br>End Date: " . $endDate . "<br>"; echo "Day Start: " . $dayStart . "<br>Day End: " . $dayEnd . "<br>"; echo "Total Days: " . $total_days . "<br>"; //////////////////////////////////////////////////////////////////////////////////// //////Then we're going to see if the dates selected are in the schedule table////// //////////////////////////////////////////////////////////////////////////////////// //Select all of the dates currently in the schedule table between the range selected. $sql = ("SELECT Date FROM schedule WHERE Date BETWEEN '$startDate' AND '$endDate' LIMIT $total_days"); //Run a check on the query to make sure it worked. If it failed then print the error. if(!$result_date_query = $mysqli->query($sql)) { die('There was an error getting the dates from the schedule table [' . $mysqli->error . ']'); } //Set the dates to an array for future use. // $current_dates = $result_date_query->fetch_assoc(); //Loop through the results while a result is being returned. while($row = $result_date_query->fetch_assoc()) { echo "Row: " . $row['Date'] . "<br>"; echo "Start day: " . date('Y-m-d', $dayStart) . "<br>"; //Set this loop to add 1 day to the Start Date until it reaches the End Date for($i = $dayStart; $i <= $dayEnd; $i = strtotime('+1 day', $i)) { $date = date('Y-m-d',$i); echo "Loop Start day: " . date('Y-m-d', $dayStart) . "<br>"; //Run a check to see if any of the dates selected are in the schedule table. if($row['Date'] != $date) { echo "Current Date: " . $row['Date'] . "<br>"; echo "Date: " . $date . "<br>"; echo "It appears as though you've selected some dates that are not in the schedule database.<br>Please correct the issue and try again."; return; } } } //Free the result so something else can use it. $result_date_query->free(); As you can see I've added in some echo statements so I can see what is being produced. From what I can see it looks like my $row['Date'] is not incrementing and staying at the same date. I originally had it set to a variable (currently commented out) but I thought that could be causing problems. I have created the table with dates ranging from 2012-11-01 to 2012-11-15 for testing and entered all of this php code onto phpfiddle.org but I can't get the username provided to connect. Here is the link: PHP Fiddle I'll be reading through the documentation to try and figure out the user connection problem in the meantime, I would really appreciate any direction or advice you can give me.

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  • Indexed key vs indexed separate columns, which one is faster ?

    - by Jerry
    In MYSQL, from a pure performance perspective, if I have a table with large amount of data with 10/1 read/write ratio. is it faster in read/write performance to have 4 search criteria in separate columns and all indexed or have them combined in to one single string acting as a key and store in one indexed column ? e.g. say this table with 5 columns, first name, last name, sex, country and file where the first four columns will ALWAYS be given as a part of search parameters in a search or have a table with two columns, key and file. where the value of key can be john-smith-male-australia ?? I don't quite get the pros and cons. the point I try to stress is the fact that all parameters will be given.in a search.

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  • Unique constraint on more than 10 columns

    - by tk
    I have a time-series simulation model which has more than 10 input variables. The number of distinct simulation instances would be more than 1 million, and each simulation instance generates a few output rows every day. To save the simulation result in a relational database, i designed tables like this. Table SimulationModel { simul_id : integer (primary key), input0 : string or numeric, input1 : string or numeric, ...} Table SimulationOutput { dt : DateTime (primary key), simul_id : integer (primary key), output0 : numeric, ...} My question is, is it fine to put an unique constraint on all of the input columns of SimulationModel table? If it is not a good idea, then what kind of other options do i have to make sure each model is unique?

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  • Why MySQL multiple-column index is overpopulated?

    - by actual
    Consider following MySQL table: CREATE TABLE `log` ( `what` enum('add', 'edit', 'remove') CHARACTER SET ascii COLLATE ascii_bin NOT NULL, `with` int(10) unsigned NOT NULL, KEY `with_what` (`with`,`what`) ) ENGINE=InnoDB; INSERT INTO `log` (`what`, `with`) VALUES ('add', 1), ('edit', 1), ('add', 2), ('remove', 2); As I understand, with_what index must have 2 unique entries on its first with level and 3 unique entries in what "subindex". But MySQL reports 4 unique entries for each level. In other words, number of unique elements for each level is always equal to number of rows in log table. Is that a bug, a feature or my misunderstanding?

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  • CodeIgniter Active Record Queries W/ Sub Queries

    - by Mike
    Question: I really am trying to stick to using ActiveRecord and not using straight SQL.. can someone help me convert this to activerecord? Trying to get the email address and contact name from another table. map_userfields table is a one to many, multiple rows per p.id. one row per p.id per uf.fieldid. see this screenshot for a reference to the map_userfields table: Current Non active record query SELECT p.id, (SELECT uf.fieldvalue FROM map_userfields uf WHERE uf.pointid = p.id AND uf.fieldid = 20) As ContactName, (SELECT uf.fieldvalue FROM map_userfields uf WHERE uf.pointid = p.id AND uf.fieldid = 31) As ContactEmail FROM map_points p WHERE /** $pointCategory is an array of categories to look for **/ p.type IN($pointCategory) Note: I am using CodeIgniter 2.1.x, MySQL 5.x, php 5.3

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  • How to use SQL trigger to record the affected column's row number

    - by Freeman
    I want to have an 'updateinfo' table in order to record every update/insert/delete operations on another table. In oracle I've written this: CREATE TABLE updateinfo ( rnumber NUMBER(10), tablename VARCHAR2(100 BYTE), action VARCHAR2(100 BYTE), UPDATE_DATE date ) DROP TRIGGER TRI_TABLE; CREATE OR REPLACE TRIGGER TRI_TABLE AFTER DELETE OR INSERT OR UPDATE ON demo REFERENCING NEW AS NEW OLD AS OLD FOR EACH ROW BEGIN if inserting then insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'insert',sysdate); elsif updating then insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'update',sysdate); elsif deleting then insert into updateinfo(rnumber,tablename,action,update_date ) values(rownum,'demo', 'delete',sysdate); end if; -- EXCEPTION -- WHEN OTHERS THEN -- Consider logging the error and then re-raise -- RAISE; END TRI_TABLE; but when checking updateinfo, all rnumber column is zero. is there anyway to retrieve the correct row number?

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  • How to achieve "merge" of two data sets with Insert SQL statemen (Oracle DBMS)t?

    - by Roman Kagan
    Hi: What would be the insert SQL statement to merge data from two tables. For example I have events_source_1 table (columns: event_type_id, event_date) and events_source_2 table (same columns) and events_target table (columns: event_type_id, past_event_date nullalbe, future_event_date nullable). Events_source_1 has past events, Events_source_2 has future events and resultant events_target would contain past and future events in the same row for same event_type_id. If there is no past_events but future_events then past_event_date won't be set and only future_event_date will be and the opposite is true too. Thanks a lot in advance for helping me resolving this problem.

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