I want to execute the following:
I have an Assignment table with an OriginID, assignmentID and assignmentname:
OriginID
AssignmentID
AssignmentName
and an AssignmentParticipant table containing two rows:
AssignmentParticipantID
AssignmentID (FK to assignment)
ParticipantName
And using a trigger on insert on another table (Graduation) I want to copy those records over. Its not a reference and I'm aware of the double data, but in this case it's necessary. So I need to copy all AssignmentName over to the GraduationName based on the OriginID, and for each new GraduationID I need to get all the original participants from that assignment and insert those into GraduationParticipant table. So there can be multiple Assignments for one originID and multiple participants to the assignment.
OriginID
GraduationID
GraduationName
and a GraduationParticipant table:
GraduationParticipantID
GraduationID (FK to Graduation)
ParticipantName
Copying the Assignments over is not an issue, but copying the list of Participants over per assignment/Graduation is throwing me for a loop. I prefer not to use a cursor but I'm not sure how to fix this in my insert trigger.
Note: I only need the ID's in the trigger, not stored on the db. So a temp table is fine i guess, but i don't know.
Related
As part of my classes on relational databases, I have to create procedures as part of package to fill some of the tables of an Oracle database I created with random data, more specifically the tables community, community_account and community_login_info (see ERD linked below). I succeeded in doing this for tables community and community_account, however I'm having some problems with generating data for table community_login_info. This serves as an intermediary table between the many to many relationship of community and community_account, linking the id's of both tables.
My latest approach was to create an associative array with the structure of the target table community_login_info. I then do a cross join of community and community_account (there's already random data in there) along with random timestamps, bulk collect that result into the variable of the associative array and then insert those contents into the target table community_login_info. But it seems I'm doing something wrong since Oracle returns error ORA-00947 'not enough values'. To me it seems all columns the target table get a value in the insert, what am I missing here? I added the code from my package body below.
ERD snapshot
PROCEDURE mass_add_rij_koppeling_community_login_info
IS
TYPE type_rec_communties_accounts IS RECORD
(type_community_id community.community_id%type,
type_account_id community_account.account_id%type,
type_start_timestamp_login community_account.start_timestamp_login%type,
type_eind_timestamp_login community_account.eind_timestamp_login%type);
TYPE type_tab_communities_accounts
IS TABLE of type_rec_communties_accounts
INDEX BY pls_integer;
t_communities_accounts type_tab_communities_accounts;
BEGIN
SELECT community_id,account_id,to_timestamp(start_datum_account) as start_timestamp_login, to_timestamp(eind_datum_account) as eind_timestamp_login
BULK COLLECT INTO t_communities_accounts
FROM community
CROSS JOIN community_account
FETCH FIRST 50 ROWS ONLY;
FORALL i_index IN t_communities_accounts.first .. t_communities_accounts.last
SAVE EXCEPTIONS
INSERT INTO community_login_info (community_id,account_id,start_timestamp_login,eind_timestamp_login)
values (t_communities_accounts(i_index));
END mass_add_rij_koppeling_community_login_info;
Your error refers to the part:
INSERT INTO community_login_info (community_id,account_id,start_timestamp_login,eind_timestamp_login)
values (t_communities_accounts(i_index));
(By the way, the complete error message gives you the line number where the error is located, it can help to focus the problem)
When you specify the columns to insert, then you need to specify the columns in the VALUES part too:
INSERT INTO community_login_info (community_id,account_id,start_timestamp_login,eind_timestamp_login)
VALUES (t_communities_accounts(i_index).community_id,
t_communities_accounts(i_index).account_id,
t_communities_accounts(i_index).start_timestamp_login,
t_communities_accounts(i_index).eind_timestamp_login);
If the table COMMUNITY_LOGIN_INFO doesn't have any more columns, you could use this syntax:
INSERT INTO community_login_info
VALUE (t_communities_accounts(i_index));
But I don't like performing inserts without specifying the columns because I could end up inserting the start time into the end time and vice versa if I haven't defined the columns in exactly the same order as the table definition, and if the definition of the table changes over time and new columns are added, you have to modify your procedure to add the new column even if the new column goes with a NULL value because you don't fill up that new column with this procedure.
PROCEDURE mass_add_rij_koppeling_community_login_info
IS
TYPE type_rec_communties_accounts IS RECORD
(type_community_id community.community_id%type,
type_account_id community_account.account_id%type,
type_start_timestamp_login community_account.start_timestamp_login%type,
type_eind_timestamp_login community_account.eind_timestamp_login%type);
TYPE type_tab_communities_accounts
IS TABLE of type_rec_communties_accounts
INDEX BY pls_integer;
t_communities_accounts type_tab_communities_accounts;
BEGIN
SELECT community_id,account_id,to_timestamp(start_datum_account) as start_timestamp_login, to_timestamp(eind_datum_account) as eind_timestamp_login
BULK COLLECT INTO t_communities_accounts
FROM community
CROSS JOIN community_account
FETCH FIRST 50 ROWS ONLY;
FORALL i_index IN t_communities_accounts.first .. t_communities_accounts.last
SAVE EXCEPTIONS
INSERT INTO community_login_info (community_id,account_id,start_timestamp_login,eind_timestamp_login)
values (select community_id,account_id,start_timestamp_login,eind_timestamp_login
from table(cast(t_communities_accountsas type_tab_communities_accounts)) a);
END mass_add_rij_koppeling_community_login_info;
I have a rather complicated (at least for me) stored procedure to write that needs to handle multiple scenarios coming from the front end.
The frontend is passing 2 parameters that has values like this
#Levelmarker= (1234515-564546-65454,4654342-154658-56767,5465489-546549-65456)
These are GUIDS that are comma separated.
#`UserNameId= (5797823-65432143-65451213)
GUID of the user that entered this data on the front end
The values need to go to a table that has the following structure:
CREATE TABLE LevelTable
(
LevelId uniqueidentifier NOT NULL
LevelMarker uniqueidentiriet NOT NULL
UserName uniqueidentifier NOT NULL
);
I want the value to go into the table like this:
LevelId Levelmarker UserName
--------------------------------------------------------
NEWID() 1234515-564546-65454 5797823-654321-65451
NEWID() 4654342-154658-56767 5797823-654321-65451
NEWID() 5465489-546549-65456 5797823-654321-65451
Here are the scenarios the stored procedure should handle.
Once the levelmarkers are inserted into the table, if the same user comes back and wants to add additional Levelmarkers, the front end will pass the old values and the new ones as so: (1234515-564546-65454,4654342-154658-56767,5465489-546549-65456,1332245-9852135-7841265).
My stored procedure should recognize that I already have the first three Levelmarkers in the table and should only insert the new ones.
If the same user decides to delete values from before, lets say two values as an example, the front end will pass me the values (1234515-564546-65454,4654342-154658-56767). The stored procedure should recognize that the user has deleted two values and should delete the same values from the table and keep the non deleted ones.
If the user deletes some values and inserts a new ones, then the stored procedure should recognize the ones to delete and insert the new ones.
What is the best approach to this problem?
I think you can do this in a single query, using string_split() and a merge statement:
merge leveltable t
using (
select value levelmarker, #UserNameId username
from string_split(#LeveMarker, ',')
) s
on (s.levelmarker = t.levelmarker and s.username = t.username)
when not matched by target
then insert (leveid, levelmarker, username)
values (newid(), s.levelmarker, s.username)
when not matched by source
then delete
In the using clause, we split the #LevelMarker parameter into new rows, and associate the given #UserNameId. Then, the merge statement checks if each combination already exists in the target table, and creates or deletes rows accordingly.
I want a list of properties about a given table and for a specific record of data from that table - in one result
Something like this:
Column Name , DataLength, SchemaLengthMax
...and for only one record (based on a where filter)
So what Im thinking is something like this:
- Get a list of columns from sys.columns and also the schema-based maxlength value
- populate column names into a temp table that includes (column_name, data_length, schema_size_max)
- now loop over that temp table and for each column name, fetch the data for that column based on a specific record, then update the temp table with the length of this data
- finally, select from the temp table
sound reasonable?
Yup. That way works. Not sure if it's the best, since it involves one iteration per column along with the where condition on the source table.
Consider this, instead :
Get the candidate records into a temporary table after applying the where condition. Make sure to get a primary key. If there is no primary key, get a rowid. (assuming SQL Server 2005 or above).
Create a temporary table (Say, #RecValueLens) that has three columns : Primary_key_Value, MyColumnName, MyValueLen
Loop through the list of column names (after taking only the column names into another temporary table) and build sql statement shown in Step 4.
Insert Into #RecValueLens (Primary_Key_Value, MyColumnName, MyValueLen)
Select Max(Primary_Key_Goes_Here), Max('Column_Name_Goes_Here') as ColumnName, Len(Max(Column_Name)) as ValueMyLen From Source_Table_Goes_Here
Group By Primary_Key_Goes_Here
So, if there are 10 columns, you will have 10 insert statements. You could either insert them into a temporary table and run it as a loop. If the number of columns is few, you could concatenate all statements into a single batch.
Run the SQL Statement(s) from above. So, you have Record-wise, column-wise, Value lengths. What is left is to get the column definition.
Get the column definition from sys.columns into a temporary table and join with the #RecValueLens to get the output.
Do you want me to write it for you ?
I am very new to SQL and SQL server, would appreciate any help with the following problem.
I am trying to update a share price table with new prices.
The table has three columns: share code, date, price.
The share code + date = PK
As you can imagine, if you have thousands of share codes and 10 years' data for each, the table can get very big. So I have created a separate table called a share ID table, and use a share ID instead in the first table (I was reliably informed this would speed up the query, as searching by integer is faster than string).
So, to summarise, I have two tables as follows:
Table 1 = Share_code_ID (int), Date, Price
Table 2 = Share_code_ID (int), Share_name (string)
So let's say I want to update the table/s with today's price for share ZZZ. I need to:
Look for the Share_code_ID corresponding to 'ZZZ' in table 2
If it is found, update table 1 with the new price for that date, using the Share_code_ID I just found
If the Share_code_ID is not found, update both tables
Let's ignore for now how the Share_code_ID is generated for a new code, I'll worry about that later.
I'm trying to use a merge query loosely based on the following structure, but have no idea what I am doing:
MERGE INTO [Table 1]
USING (VALUES (1,23-May-2013,1000)) AS SOURCE (Share_code_ID,Date,Price)
{ SEEMS LIKE THERE SHOULD BE AN INNER JOIN HERE OR SOMETHING }
ON Table 2 = 'ZZZ'
WHEN MATCHED THEN UPDATE SET Table 1.Price = 1000
WHEN NOT MATCHED THEN INSERT { TO BOTH TABLES }
Any help would be appreciated.
http://msdn.microsoft.com/library/bb510625(v=sql.100).aspx
You use Table1 for target table and Table2 for source table
You want to do action, when given ID is not found in Table2 - in the source table
In the documentation, that you had read already, that corresponds to the clause
WHEN NOT MATCHED BY SOURCE ... THEN <merge_matched>
and the latter corresponds to
<merge_matched>::=
{ UPDATE SET <set_clause> | DELETE }
Ergo, you cannot insert into source-table there.
You could use triggers for auto-insertion, when you insert something in Table1, but that will not be able to insert proper Shared_Name - trigger just won't know it.
So you have two options i guess.
1) make T-SQL code block - look for Stored Procedures. I think there also is a construct to execute anonymous code block in MS SQ, like EXECUTE BLOCK command in Firebird SQL Server, but i don't know it for sure.
2) create updatable SQL VIEW, joining Table1 and Table2 to show last most current date, so that when you insert a row in this view the view's on-insert trigger would actually insert rows to both tables. And when you would update the data in the view, the on-update trigger would modify the data.
Here is the following situation:
I have a table of StudentsA which needs to be synchronized with another table, on a different server, StudentsB. It's a one-way sync from A to B.
Since the table StudentsA can hold a large number of rows, we have a table called StudentsSync (on the input server) containing the ID of StudentsA which have been modified since the last copy from StudentsA to StudentsB.
I made the following SSIS Data Flow task:
The only problem is that I need to DELETE the row from StudentsSync after a successful copy or update. Something like this:
Any idea how this can be achieved?
It can be achieved using 3 methods
1.If your target table in OutputDB has TimeStamp columns such as Create and modified TimeStamp then rows which have got updated or inserted can be obtained by writing a simple query. You need to write the below query in the execte sql task in Control Flow to delete those rows in Sync Table .
Delete from SyncTable
where keyColumn in (Select primary_key from target
where ModifiedTimeStamp >= GETDATE() or (ModifiedTimeStamp is null
and CreateTimeStamp>=GETDATE()))
I assume StudentsA's primary key is present in Sync table along with primary key of Target table. The above condition basically checks, if a new row is added then CreateTimeStamp column will have current date and modifiedTimeStamp will be null else if the values are updated then the modifiedTimeStamp will have current date
The above query will work if you have TimeStamp columns in your target table which i feel should be there if your loading data into Data Warehouse
2.You can use MERGE syntax to perform the update and insert in Control Flow with Execute SQL Task.No need to use Data Flow Task .The below query can be used even if you don't have any TimeStamp columns
DECLARE #Output TABLE ( ActionType VARCHAR(20), SourcePrimaryKey INT)
MERGE StudentsB AS TARGET
USING StudentsA AS SOURCE
ON (TARGET.CommonColumn = SOURCE.CommonColumn)
WHEN MATCHED
THEN
UPDATE SET TARGET.column = SOURCE.Column,TARGET.ModifiedTimeStamp=GETDATE()
WHEN NOT MATCHED BY TARGET THEN
INSERT (col1,col2,Col3)
VALUES (SOURCE.col1, SOURCE.col2, SOURCE.Col3)
OUTPUT $action,
INSERTED.PrimaryKey AS SourcePrimaryKey INTO #Output
Delete from SyncTable
where PrimaryKey in (Select SourcePrimaryKey from #Output
where ActionType ='INSERT' or ActionType='UPDATE')
The code is not tested as i'm running out of time .but at-least it should give you a fair idea how to proceed . .For furthur detail on MERGE syntax read this and this
3.Use Multicast Component to duplicate the dataset for Insert and Update .Connect a MULTICAST to lookmatch output and another multicast to Lookup No match output
Add a task after "Update existing entry" and after "Insert new entry" to add the student ID to a variable which will contain the list of IDs to delete.
Enclose all of the tasks in a sequence container.
After the sequence container executes add a task to delete all the records from the sync table that are in that variable you've been populating.