I'm probably making a stupid beginner mistake here but SQL isn't one of my strong points.
I'm trying to modify a simple SQLite DB (in SQLite Manager) but can't seem to do it until I figure out why I can't get this select statement to return.
SELECT *
FROM facts
WHERE id = -9215979828305747000
threw no error and returned nothing regardless of the fact that its the first entry on the table. I also tried
SELECT *
FROM facts
WHERE CAST(facts.id AS INTEGER) = CAST('-9215979828305747000' AS INTEGER)
again nothing.
I see the value in the browse window but can't get it in a specific search. Is this happening because of value length?
-9215979828305747000 is bigger than the maximum value for an Int32 (2147483647), so I guess facts.id is not an Integer. Check your datatype and CAST accordingly.
Perhaps it is a string?
SELECT *
FROM facts
WHERE id = '-9215979828305747000'
I did this test :
CREATE TABLE "test" (
"id" INTEGER PRIMARY KEY NOT NULL,
"name" TEXT
)
insert into test values (1, "tttt")
insert into test values (-9215979828305747000, "OO")
select name from test where id = -9215979828305747000'
> "OO"
So it seems to work in a fresh new table. The problem is clearly not in the sql select or key or table definition.
Try to get the data in some temporary table :
insert into table_copy values (select * from facts)
Related
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.
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'm trying to avoid writing separate SQL queries to achieve the following scenario:
I have a Table called Values:
Values:
id INT (PK)
data TEXT
I would like to check if certain data exists in the table, and if it does, return its id, otherwise insert it and return its id.
The (very) naive way would be:
select id from Values where data = "SOME_DATA";
if id is not null, take it.
if id is null then:
insert into Values(data) values("SOME_DATA");
and then select it again to see its id or use the returned id.
I am trying to make the above functionality in one line.
I think I'm getting close, but I couldn't make it yet:
So far I got this:
select id from Values where data=(COALESCE((select data from Values where data="SOME_DATA"), (insert into Values(data) values("SOME_DATA"));
I'm trying to take advantage of the fact that the second select will return null and then the second argument to COALESCE will be returned. No success so far. What am I missing?
Your command does not work because in SQL, INSERT does not return a value.
If you have a unique constraint/index on the data column, you can use that to prevent duplicates if you blindly insert the value; this uses SQLite's INSERT OR IGNORE extension:
INSERT OR IGNORE INTO "Values"(data) VALUES('SOME_DATE');
SELECT id FROM "Values" WHERE data = 'SOME_DATA';
I have MSSQL table having columns, serves as storage for items for user with certain name. Each user have one record in table Items that looks like that:
Name(string) 1(string) 2(string) 3(string) 4(string) 5(string)
When inserting data, I would need to use the column ("packet") ona by one. Meaning if "1" contains data, use column "2". If "1" is empty, use "1". If only "3" is empty, use "3"/
In other words, I always need to select the lowest empty column to write the data in. If none of these 5 is empty, then do not write data at all.
Could anyone help me with that query? Thank you
The correct way to model this in SQL would be:
CREATE TABLE Tab (
Name varchar(20) not null, --20? Who knows, not specced in question
Idx int not null,
Value varchar(20) not null, --20? Who knows, not specced in question
constraint PK_Tab PRIMARY KEY (Name,Idx),
constraint CK_Tab_Indexes CHECK (Idx between 1 and 5)
)
You could then write your insert as:
INSERT INTO Tab (Name,Idx,Value)
SELECT #Name,COALESCE((select MAX(Idx)+1 from Tab where Name=#Name),1),#Value
where #Name and #Value are the supplied values to insert. If there are already 5 items in the table for a particular name, you'll get a check constraint error and the insert will fail.
This also makes querying for particular values possible, without having to search 5 different columns, and it means that extending to more items in the future far easier (by just changing the check constraint)
I'd had the impression that this was insert only. If deletions are occurring, and you want to reuse items, then the insert query would be:
;WITH Nums(n) as (select 1 union all select 2 union all select 3 union all select 4 union all select 5)
INSERT INTO Tab (Name,Idx,Value)
SELECT #Name,(select MIN(n) from Nums where not exists (select * from Tab where Name=#Name and Idx = n)),#Value
which will now fail because of a not-null constraint once you're up at 5 items. It could be simpler if you already have a numbers table in your database, but I've assumed not above.
I have the following hsqldb table, in which I map UUIDs to auto incremented IDs:
SHORT_ID (BIG INT, PK, auto incremented) | UUID (VARCHAR, unique)
Create command:
CREATE TABLE mytable (SHORT_ID BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY, UUID VARCHAR(36) UNIQUE)
In order to add new pairs concurrently, I want to use the atomic MERGE INTO statement. So my (prepared) statement looks like this:
MERGE INTO mytable USING (VALUES(CAST(? AS VARCHAR(36)))) AS v(x) ON mytable.UUID = v.x WHEN NOT MATCHED THEN INSERT VALUES v.x
When I execute the statement (setting the placeholder correctly), I always get a
Caused by: org.hsqldb.HsqlException: row column count mismatch
Could you please give me a hint, what is going wrong here?
Thanks in advance.
Epilogue
I reported this behavior as a bug, and it is today (2010-05-25) fixed in the hsqldb SVN repository, per hsqldb-Bugs-2989597. (Thanks, hsqldb!)
Updated Answer
Neat one! Here's what I got to work under HSQLDB 2.0.0rc9, which supports the syntax and the error message you posted:
MERGE INTO mytable
USING (SELECT 'a uuid' FROM dual) AS v(x) -- my own "DUAL" table
ON (mytable.UUID = v.x)
WHEN NOT MATCHED THEN INSERT
VALUES (NULL, x) -- explicit NULL for "SHORT_ID" :(
Note, I could not convince 2.0.0rc9 to accept ... THEN INSERT (UUID) VALUES (x), which is IIUC a perfectly acceptable and clearer specification than the above. (My SQL knowledge is hardly compendious, but this looks like a bug to me.)
Original Answer
You appear to be INSERTing a single value (a 1-tuple) into a table with more than one column. Perhaps you can modify the end of your statement to read:
... WHEN NOT MATCHED INSERT ("UUID") VALUES (v.x)
I got same problems but solve in few minutes.
Its occur when datavalues and table structure are not same.Add explicit (NULL) in your empty column value.
Like i created table
TestCase table:
ID TESTCASEID DESCRIPTION
but your insertion statement you donot want to add any description for any testcase description then you have to explicite in insertion statement you have to set null value for description