I'm trying to find a query for sql that will just insert values but not do it should the value exist. Now ive seen alot of examples but they all rely on primary keys or table to table moves. I just want to add a new row in the table and assuming that one of the collumns doesnt have the same value add it. I know the following wont work but its as close to I think it would be and might just clear it up if my writting is not enough.
INSERT INTO table (txtLastName,txtEmail,txtZip)
Values ('Tester','test#test.com','12345')
WHERE txtLastName <> 'Tester'
or WHERE txtEmail <> 'test#test.com'
or WHERE txtZip <> '12345'
Using MS SQL Server.
You should create a Unique Constraint composed by the three fields (txtLastName, txtEmail, txtZip).
The links directs you to SQL Server docs, but the concept of unique constraint is RDBMS universal.
Just beware that when you create a Unique Constraint, your duplicate insert will not just fail silently: it will throw an error saying the insert tried to violate the unique constraint. And, of course, it should do that! Make sure your code handles that exception.
Try this:
INSERT INTO table (txtLastName,txtEmail,txtZip)
SELECT 'Tester','test#test.com','12345'
WHERE NOT EXISTS (SELECT *
FROM table
WHERE txtLastName = 'Tester'
AND txtEmail = 'test#test.com'
AND txtZip = '12345'
)
Related
I have had a look at similar problems, however none of the answers helped in my case.
Just a little bit of background. I have Two databases, both have the same table with the same fields and structure. Data already exists in both tables. I want to overwrite and add to the data in db1.table from db2.table the primary ID is causing a problem with the update.
When I use the query:
USE db1;
INSERT INTO db2.table(field_id,field1,field2)
SELECT table.field_id,table.field1,table.field2
FROM table;
It works to a blank table, because none of the primary keys exist. As soon as the primary key exists it fails.
Would it be easier for me to overwrite the primary keys? or find the primary key and update the fields related to the field_id? Im really not sure how to go ahead from here. The data needs to be migrated every 5min, so possibly a stored procedure is required?
first you should try to add new records then update all records.you can create a procedure like below code
PROCEDURE sync_Data(a IN NUMBER ) IS
BEGIN
insert into db2.table
select *
from db1.table t
where t.field_id not in (select tt.field_id from db2.table tt);
begin
for t in (select * from db1.table) loop
update db2.table aa
set aa.field1 = t.field1,
aa.field2 = t.field2
where aa.field_id = t.field_id;
end loop;
end;
END sync_Data
Set IsIdentity to No in Identity Specification on the table in which you want to move data, and after executing your script, set it to Yes again
I ended up just removing the data in the new database and sending it again.
DELETE FROM db2.table WHERE db2.table.field_id != 0;
USE db1;
INSERT INTO db2.table(field_id,field1,field2)
SELECT table.field_id,table.field1,table.field2
FROM table;
Its not very efficient, but gets the job done. I couldnt figure out the syntax to correctly do an UPDATE or to change the IsIdentity field within MariaDB, so im not sure if they would work or not.
The overhead of deleting and replacing non-trivial amounts of data for an entire table will be prohibitive. That said I'd prefer to update in place (merge) over delete /replace.
USE db1;
INSERT INTO db2.table(field_id,field1,field2)
SELECT t.field_id,t.field1,t.field2
FROM table t
ON DUPLICATE KEY UPDATE field1 = t.field1, field2 = t.field2
This can be used inside a procedure and called every 5 minutes (not recommended) or you could build a trigger that fires on INSERT and UPDATE to keep the tables in sync.
INSERT INTO database1.tabledata SELECT * FROM database2.tabledata;
But you have to keep length of varchar length larger or equal to database2 and keep the same column name
I want to add another row in my existing table and I'm a bit hesitant if I'm doing the right thing because it might skew the database. I have my script below and would like to hear your thoughts about it.
I want to add another row for 'Jane' in the table, which will be 'SKATING" in the ACT column.
Table: [Emp_table].[ACT].[LIST_EMP]
My script is:
INSERT INTO [Emp_table].[ACT].[LIST_EMP]
([ENTITY],[TYPE],[EMP_COD],[DATE],[LINE_NO],[ACT],[NAME])
VALUES
('REG','EMP','45233','2016-06-20 00:00:00:00','2','SKATING','JANE')
Will this do the trick?
Your statement looks ok. If the database has a problem with it (for example, due to a foreign key constraint violation), it will reject the statement.
If any of the fields in your table are numeric (and not varchar or char), just remove the quotes around the corresponding field. For example, if emp_cod and line_no are int, insert the following values instead:
('REG','EMP',45233,'2016-06-20 00:00:00:00',2,'SKATING','JANE')
Inserting records into a database has always been the most common reason why I've lost a lot of my hairs on my head!
SQL is great when it comes to SELECT or even UPDATEs but when it comes to INSERTs it's like someone from another planet came into the SQL standards commitee and managed to get their way of doing it implemented into the final SQL standard!
If your table does not have an automatic primary key that automatically gets generated on every insert, then you have to code it yourself to manage avoiding duplicates.
Start by writing a normal SELECT to see if the record(s) you're going to add don't already exist. But as Robert implied, your table may not have a primary key because it looks like a LOG table to me. So insert away!
If it does require to have a unique record everytime, then I strongly suggest you create a primary key for the table, either an auto generated one or a combination of your existing columns.
Assuming the first five combined columns make a unique key, this select will determine if your data you're inserting does not already exist...
SELECT COUNT(*) AS FoundRec FROM [Emp_table].[ACT].[LIST_EMP]
WHERE [ENTITY] = wsEntity AND [TYPE] = wsType AND [EMP_COD] = wsEmpCod AND [DATE] = wsDate AND [LINE_NO] = wsLineno
The wsXXX declarations, you will have to replace them with direct values or have them DECLAREd earlier in your script.
If you ran this alone and recieved a value of 1 or more, then the data exists already in your table, at least those 5 first columns. A true duplicate test will require you to test EVERY column in your table, but it should give you an idea.
In the INSERT, to do it all as one statement, you can do this ...
INSERT INTO [Emp_table].[ACT].[LIST_EMP]
([ENTITY],[TYPE],[EMP_COD],[DATE],[LINE_NO],[ACT],[NAME])
VALUES
('REG','EMP','45233','2016-06-20 00:00:00:00','2','SKATING','JANE')
WHERE (SELECT COUNT(*) AS FoundRec FROM [Emp_table].[ACT].[LIST_EMP]
WHERE [ENTITY] = wsEntity AND [TYPE] = wsType AND
[EMP_COD] = wsEmpCod AND [DATE] = wsDate AND
[LINE_NO] = wsLineno) = 0
Just replace the wsXXX variables with the values you want to insert.
I hope that made sense.
I want to copy all columns from dbo.die to dbo.technology.
Both tables exist! In dbo.technology, the primary key is idTechnology
In dbo.die, the primary key is idDie and we have a foreign key, which is Technology_idTechnology in it, which connects the die table with the technology table.
How could I do that, so that the values got copied to the right rows, which match the same idTechnology?
I tried this:
INSERT INTO dbo.die
(Technology_idTechnology, Technology_D, Technology_Type, Technology_Manufacturer, Technology_SOI, Technology_Node, Technology_Name, Technology_Number_Metal, Technology_Number_Poly, Technology_Power_Cu, Technology_FEComplexity, Technology_FEComplexity_Sec, Technology_Trench, Technology_IMID, Technology_Remarks)
SELECT *
FROM dbo.technology tech
WHERE tech.idTechnology = idTechnology;
but I'm always getting an error!
Cannot insert duplicate key row in object 'dbo.die' with unique index 'ui_dieIdsample'. The duplicate key value is ().
Don't know what I should do.. I thought it's easy & simple
If a column is declared as NOT NULL (and has no default value), a value for the column must be specified in the INSERT statement.
In this specific case you should add Table2_Feld to the insert column list, and specify a value in the SELECT for it!
You will need to change your column list (lets say that its acceptable to insert a default value of 0 into column Table2_Feld)
INSERT INTO dbo.table2
(Table1_idTech, Tech_D, Techn_Type, Tech_Man,
Techn_Node, Tech_Name, Technology_Numb, Tech_Po,
Tech_FEC, Techn_Comp_Sec,
Tech_R,Table2_Feld)
select *,0 from table1 tech
In a database application, I want to insert, update and delete records in a table of database.
Table is as below:
In this table, Ga1_ID is Primary Key.
Suppose, I insert 5 records as show currently.
In second attempt, if I want to insert 5 other records and if any of these new records contains a primary key attribute which is already present in table it show error. Its fine.
But, when I insert new 5 records... how I can verify these new records's primary key value is not present. I mean, how to match or calculate the already present primary key attributes and then insert new records.
What is the best approach to manage this sort of situation ?
use following query in dataadapter:
da=new SqlDataAdapter("select Ga1_ID from table where Ga1_ID=#pkVal",conn);
DataSet=new DataSet();
da.fill(ds);
//pass parameter for #pkVal
da.SelectCommand.Parameters(1).Value = pkValue;
if(ds.Tables[0].Rows.Count>0) //If number of rows >0 then record exists
BEGIN
messagebox.show("Primary key present");
END
Hope its helpful.
Do not check existing records in advance, i.e. do not SELECT and then INSERT. A better (and pretty common) approach is to try to INSERT and handle exceptions, in particular, catch a primary key violation if any and handle it.
Do the insert in a try/catch block, with different handling in case of a primary key violation exception and other sql exception types.
If there was no exception, then job's done, record was inserted.
If you caught a primary key violation exception, then handle it appropriately (your post does not specify what you want to do in this case, and it's completely up to you)
If you want to perform 5 inserts at once and want to make sure they all succeed or else roll back if any of them failed, then do the inserts within a transaction.
you can do a lookup first before inserting.
IF EXISTS (SELECT * FROM tableName WHERE GA1_id=#newId)
BEGIN
UPDATE tableName SET Ga1_docid = #newdocID, GA1_fieldNAme = #newName, Ga1_fieldValue = #newVal where GA1_id=#newId
END
ELSE
BEGIN
INSERT INTO tableName(GA1_ID, Ga1_docid, GA1_fieldNAme Ga1_fieldValue) VALUES (value1,val2,value3,value4)
END
If you're using SQL Server 2012, use a sequence object - CREATE SEQUENCE.
This way you can get the next value using NEXT VALUE FOR.
With an older SQL Server version, you need to create the primary key field as an IDENTITY field and use the SCOPE_IDENTITY function to get the last identity value and then increment it manually.
Normally, you would like to have a surrogate key wich is generally an identity column that will automatically increment when you are inserting rows so that you don't have to care about knowing which id already exists.
However, if you have to manually insert the id there's a few alternatives for that and knowing wich SQL database you are using would help, but in most SQL implementations, you should be able to do something like:
IF NOT EXISTS
IF NOT EXISTS(
SELECT 1
FROM your_table
WHERE Ga1_ID = 1
)
INSERT INTO ...
SELECT WHERE NOT EXISTS
INSERT INTO your_table (col_1, col_2)
SELECT col_1, col_2
FROM (
SELECT 1 AS col_1, 2 AS col_2
UNION ALL
SELECT 3, 4
) q
WHERE NOT EXISTS (
SELECT 1
FROM your_table
WHERE col_1 = q.col_1
)
For MS SQL Server, you can also look at the MERGE statement and for MySQL, you can use the INSERT IGNORE statement.
I want to insert a row if it doesn't already exist. If it does already exist, I want to get it's primary key.
Can this be done without using two queries, for instance using a UNIQUE constraint on the columns and ON CONFLICT ... TELL ME THE CONFLICTING ROWID?
Please note that I don't have experience with SQLite. However, after perusing the online documentation, I don't believe that it supports data-change table references, so no, this isn't possible.
My reccommendation is to write your INSERT in such a way that it won't fail if the row exists - it just won't insert a row. Something like this:
INSERT INTO destinationTable (colA, colB)
(SELECT :colAValue, :colBValue
WHERE NOT EXISTS (SELECT '1'
FROM destinationTable
WHERE uniqueColumn = :uniqueColumn))
This works because the selection won't return a row if it already exists. You can then either look at the return code/state to see if it INSERTed a row, or just SELECT with the unique column, to get the identity column.
DON'T rely on your constraint to catch this. Constraints are to catch application errors, and this is solely a business/implementation detail.
In a word, no. You can't, with SQLite, either INSERT data or, on some condition, SELECT it.
Other SQL engines might allow it, but SQLite can't.
What you can do is INSERT OR IGNORE, which will just not bring up an error. See http://sqlite.org/lang_conflict.html