Converting Empty String To Null When Inserting/updating
Mar 10, 2006
I am using the following query to calculate date differences:
select ..........DATEDIFF(d, recruitment_advertising.advertising_date, career_details.RTS_Email AS Datetime) AS Ad_to_RTS_days FROM .....
I have stored all my dates as NVARCHAR because of the issues with localization.
If the value is an empty String my output is eg: -38700. which is way off and incorrect. Some of the values in my table are NULL and they produce the correct result.
Is there a T-SQL statement to replace empy Strings with the NULL value in my tables.
I'd like to use it as a trigger when inserting or updating to convert empty strings to NULL
before the values are inserted.
Hi, What is the difference updating a null value to char/varchar type column
versus empty string to char/varchar type column?Which is the best to do and why? Could anyone explain about this?
Example:
Table 1 : tCountry - Name varchar(80) nullable Table 2 :tState - Name char(2) nullable Table 3 :tCountryDetails - countryid,state (char(2) nullable) - May the country contain state or no state So,when the state is not present for the country ,i have two options may be - null,'' tCountryDetails.State = '' or tCountryDetails.State = null?
We are writing a C application that is using ODBC to insert recordsinto a database. We have a NOT NULL column that can legitimately havean empty value, i.e. we know the value and it is empty (i.e. a zerolength string).We are using SQLBindParameter() to bind a variable to theparameterized insert statement <<in the form: INSERT INTO table VALUES(?, ?, ?)>>. We are using SQLExecDirect() to process the SQL.We are running into the problem where ODBC is converts the empty (zerolength) string into a NULL value and this errors due to the fact thatthe column is defined as NOT NULL.We do not want to redefine the column as NULL, becasue myunderstanding of the correct usage of a NULL column is to indicatethat a value is unknown or meaningless... in our case we know thevalue (it is empty) and an empty value has meaning within ourapplication.I'm sure that this issue has been seen and address thousands(millions?) of times... any guidance would be appreciated.
I'm doing a bcp out of a table to a file. Some of the fields in arecord may have an empty string.When I bcp out to the file and examine it, the fields that have anempty string in the database now show up in the file as having oneblank character.Why is bcp doing this? I don't want the blank character in my output.Thanks,Eric
I need to check in my Stored procedure if the information passed is null or empty so I can decided to insert the new value or keep the old. How do I accomplish this please in T-SQL. Thanks in advance.
Hi: Trying to insert null value into sql table, but not working, if I use: if (strMyText.Length == 0) command.Parameters.Add("@Text", DBNull.Value); // or using:("@Text", null), or using:("@Text", DBNull) else command.Parameters.AddWithValue("@Text", strMyText); When I go back to table, I see the value is: 'NULL', has single quotation mark, suppose to be: NULL Where is the problem? Thanks a lot. Jt
Hi all, I have some columns in my database which allows null. I want to know if leaving the field to be NULL or storing an empty string into the field, which will take up more space?? if the field type is varchar(100)
I've have about 100 tables, for some reasons, column values that are originally NULL was inserted as emtpy string. So, I am wondering if I can write JUST ONE SQL (hopefully don't have to specify the field names in the SQL as well) for each table so that all the empty strings will be converted back to NULL.
Hi all,I have this code that I use for my Search function:SELECT DISTINCT [MUSIC_TITLE], [MUSIC_ORIGINAL_SINGER], [MUSIC_PERFORMER]FROM t_musicWHERE (@MUSIC_TITLE IS NULL OR [MUSIC_TITLE] LIKE '%' + @MUSIC_TITLE + '%') AND (@MUSIC_ARTIST IS NULL OR ([MUSIC_ORIGINAL_SINGER] LIKE '%' + @MUSIC_ARTIST + '%' OR [MUSIC_PERFORMER] LIKE '%' + @MUSIC_ARTIST + '%')) But right now if I don't enter anything in one of the textbox (2 have two, either of them can be left empty), the above Sql statement doesn't return anything since ADO.NET can't tell an empty textbox and treat it at null... So anyone please help me how to detect an empty textbox and set that to null for the above SQL statement to work. (It work in SQL Manager Studio, when I set one of the parameter = null.) I'm very new to ASP.NET stuffs, so if someone can help me to convert that function to code-behind and help me to call it from the .aspx, that would be even better as I don't want to put the code in my .aspx page... But I'm not quite there yet. Thank you all,Kenny.
i have a trigger on a table right now... when fields are inserted, theres a text field inserted and i want to check if that text field = '' (the empty string, not NULL) and if it doesn't equal that, then perform some row updates on other tables, but if it is empty, to not do anything else in the trigger... right now i have this:
Code:
IF ((SELECT Note FROM XATPoDetail WHERE ReqNbr = (SELECT ReqNbr FROM Inserted)) LIKE(''))
Note is the text field, XATPoDetail is the table where its being inserted into. I had to do the select FROM the table because it wouldn't let me select a text data type from the "Inserted" virtual table
but it tells me me "Error 279: The text, ntext, and image data types are invalid in this subquery or aggregate expression"
i have a trigger on a table right now... when fields are inserted, theres a text field inserted and i want to check if that text field = '' (the empty string, not NULL) and if it doesn't equal that, then perform some row updates on other tables, but if it is empty, to not do anything else in the trigger... right now i have this:
IF ((SELECT Note FROM XATPoDetail WHERE ReqNbr = (SELECT ReqNbr FROM Inserted)) LIKE(''))
Note is the text field, XATPoDetail is the table where its being inserted into. I had to do the select FROM the table because it wouldn't let me select a text data type from the "Inserted" virtual table
but it tells me me "Error 279: The text, ntext, and image data types are invalid in this subquery or aggregate expression"
Ok.. so I have a fixed position data feed. I read the file in as just whole rows initially, process a specific position and evaluate a conditional split to determine direction of the file for proper processing (file contains multiple recors with different layouts). This all works fine. I then use the derived column feature to process all the columns.
Most of the columns are as simple as SUBSTRING(RecordData,1,10) for example to get the first column. This all works for string data. I then have a column that is a date field. The problem occurs that the code SUBSTRING(RecordData,20,10) returns either a date or empty set of data if no date was in the original file. When this gets sent to the OLEDB connection (SQL Server 2005) into the date field it fails. If the record has a date it works, but if it is empty it fails the insert.
I tried to replace empty strings with NULLs with this code. REPLACE(TRIM(SUBSTRING(RecordData,20,10)),"",NULL(DT_WSTR,10)). This does not work. So my question is how do I bring a date field from a fixed flat file into a SQL datetime field using a derived column? More specifically is how do I set it to NULL if its empty data? When I use the above code it inserts all the rows from the file, but it sets all rows to NULL not just the empty ones.
In my source table, I have columns FirstName and LastName, both of datatype nvarchar. In my dataflow, I created two new derived columns mapped to these two columns. When pushing data to the source, I noticed that the FirstName column had a value of NULL while LastName was just an empty string (for rows that did not have any value).
My question is, why my source table column FirstName is showing a NULL value when the derived column datatype is string and the source is string? It should just be showing an empty string right?
In SSIS flat file import using fastload, I'm trying to import data into SQL 2005 previously created tables.
The table may contain column that are NULLable BUT there is NO DEFAULT for them.
If the incoming data from flat files contains nothing either between the delimeters, how can I have a NULL value inserted in the column instead of blank/empty string?
I didn't find an easy flag unless I'm doing something wrong. I know of at least two ways to do it the hard way:
1- set the DEFAULT(NULL) for EVERY column that needs this behaviour
2-set up some Derived Column option in the package to return NULL if the value is missing.
Both of the above are time consuming since I'm dealing with many tables. Is there a quick option to default the value to NULL WHEN there is NO data ELSE insert the data itself? So the same behavior that I have right now except that I want NULL in place of empty string/blank in the varchar(x) columns.
Folks, this isn't exactly a 'Getting Started' question, but I couldn't find a more appropriate Application Development forum.
I'm porting an open source PHP application (http://sourceforge.net/projects/gallery) to use SQL Server as a backend. One of Gallery's unit test scripts tests the ability to insert a string containing a NULL character ( ). It's OK if the string is truncated during insertion, just so long as everything before the is there.
The string being inserted looks like:
$testString = "The NULL character should be escaped !";
(Note the between "escaped " and " !")
The error that the Gallery test script is getting is:
[Microsoft][ODBC SQL Server Driver][SQL Server]Incorrect syntax near 'The NULL character should be escaped '.] in EXECUTE("INSERT INTO g2_PluginParameterMap (g_pluginType, g_pluginId, g_itemId, g_parameterName, g_parameterValue) VALUES ('module','unitTestModule',1,'test19476','The NULL character should be escaped !')")
It looks like SQL Server is complaining about the syntax. I've written a much simpler test script in the hopes of reproducing the problem, but I don't know if what I'm now hitting is the same problem or a different one.
// Connect to the db $db = new COM("ADODB.Connection") or die("Cannot start ADO"); $db->open($connectString);
// Drop & recreate the table $db->Execute ($sqlTableDrop); $db->Execute ($sqlTableCreate);
// Insert the test data //$testString = "The NULL character should be escaped !"; $testString = "This is a test string."; $res = $db->Execute("insert into ljmtemp (col1) values ('$testString')"); if (!$res) die ("INSERT failed");
// Disconnect from the db $db->Close();
?>
And it results in:
C:MyServer>php testMsSqlInsertNull.php PHP Fatal error: Uncaught exception 'com_exception' with message 'Source: Microsoft OLE DB Provider for ODBC Drivers Description: [Microsoft][ODBC SQL Server Driver][SQL Server]Unclosed quotation mark after the character string 'The NULL character should be escaped '.' in C:MyServer estMsSqlInsertNull.php:27 Stack trace: #0 C:MyServer estMsSqlInsertNull.php(27): com->Execute('insert into ljm...') #1 {main} thrown in C:MyServer estMsSqlInsertNull.php on line 27
I'm not sure if this is the same problem as Gallery is reporting or another one.
It looks like somebody is treating the as a string terminator, but when i double the backslash the literal ' ' is inserted into the database.
How can I get SQL Server to insert at least everything up to the ?
Hopefully once I have my simple script working I'll be able to figure out what's wrong in the Gallery test.
I am very new to SQL Server 2005. I have created a package to load data from a flat delimited file to a database table. The initial load has worked. However, in the future, I will have flat files used to update the table. Some of the records will need to be inserted and some will need to update existing rows. I am trying to do this from SSIS. However, I am very lost as to how to do this.
hi,my structure table in database:Amount float(53) not null default 0when i try to run his script:alter table ABC alter column Amount float(53) nullit can only set the Amount to allow null, but can't set the defaultvalue to empty.anyone know how to set the field to allow null and default set toempty, no value.thanks
Hi, is there an equivalent to the mysql's " INSERT INTO table () VALUES ();"? The fields don't allow null values, and there is a primary key with auto increment. Any ideas?Thanks a lot.
I am using VB6 and SQL7. I am asking a user to enter a date if applicable - specifically a product manufactured date. I then take that date, using the dateadd function, query a table for a specific code, and calculate an expiration date based on the particular code.
The problem - if the user does not enter a manufactured date, which is OK, SQL inserts 01/01/1900 - which I do not want. How do I handle?
I am inserting the date, if there is one, from a flexgrid. I am declaring the variable as variant. The SQL field is DateTime.
I'm trying to do a simple update like I have done countless timesbefore.However, when I update the empty fields in this table it places a -1into the field rather than the enterred value.It is indexed with duplicates allowed. It says that zero lenght isset to yes.What can I do about this?if Request.form("ouserid") <> "" Thenvar2 = " and userid = '" & Request.form("ouserid") & "' "Elsevar2 = " and userid is null "End ifif Request.form("orepid") <> "" Thenvar1 = " repid = '" & Request.form("orepid") & "'"Elsevar1 = " repid is null "End if"Update [Website Settings] set userid = '" & REquest.form("userid") &"' and repid = '" & Request.form("repid") & "' where " & var1 & var2& var3Thanks!
I have a query that returns the appropriate values I need, however there is one field I'd like to add and utilize but my problem is I only want to use it if it contains data.
If I filter it with IS NOT NULL it returns all the records, including the empty records. The field is simply empty, and doesn't come back as NULL. If I filter it with =' ' , it shows all the records with the empty records only.
I need to do the opposite, be able to filter it only if it's not empty.
I've inherited a terribly designed database. When cells in the tables have nothing in them, rather than being NULL, they're just empty. So now I can't use COALESCE...
Is there a way for COALESCE to check if a cell is empty instead of NULL? And if not, is there a way to get around this?
************* Edited by moderator Adec *************** Inserted missing < code></ code> tags. Always include such tags when including code in your postings. Don't force the moderators to do this for you. Many readers disregard postings without the code tags. **************************************************
Well met,
Let's say I have a web form that allows users to insert and update records in a SQL database. Is it better to set empty web controls (textbox, etc.) to DBNull or let it go as an empty string into the database?
I added a new field to an existing ETL process which uses SSIS to ingest a CSV file. The new field in the file, Call_Transaction_ID, will not always be populated for every record and so can be NULL or empty for certain records.
Here's the problem:After the file is extracted into a staging table, the Call_Transaction_ID field is showing blank or empty when it has no ID for that particular record. The problem is when I try to then ETL this data into a fact table - I'm trying to set the Call_Transaction_ID field to -1 if it is NULL or empty, however SQL Server doesn't see the field as empty even though there is no value in the field so -1 will NEVER return.
Using a WHERE DATALENGTH(Call_Transaction_ID) = 0 returns 0 records, again because SQL Server doesn't see the field as empty or NULL.
What do I do now to get around this? How do I fix it?
Hello,I'm a beginner in SQL and I have been searching through the SQL Cookbook and Google but I can't seem to find an example of what I want to do. I want to create a report that will return names and emails using two of my tables. I want to use the email in my primary table in the select but if it is null or empty I want to replace it with an email from my secondary table. Below is what I would like to do but I got a syntax error with it in SQL Server 2000. SELECT MemberID As ID, MemberFirstName As FirstName, MemberLastName As LastName, (IF MemberEmail = '' THEN SELECT TOP 1 OtherEmail FROM OtherTable WHERE OtherID = MemberID) As EmailFROM PrimaryTableThanks for your time.Jason
declare @user varchar(30) = '' if(@user is not null or @user <> '') BEGIN print 'I am not empty' END ELSE BEGIN print 'I am empty' ENd
The output should be 'i am empty' but when i execute this i am getting ' i am not empty'. even i did browse through but i don't find the difference in my logic.
