Executing select during bulk insert - oracle - sql

While trying to select from a table at a time when multiple insert are being made to the same table, the select statement times out. How can this be avoided

Related

Db2 sqlcode -20186

I am trying to run a simple insert statement in db2 but getting invalid statement:
my sql :
insert into schema1.table1 select * from schema2.table1
Error:
SQLCODE = -20186, ERROR: A CLAUSE SPECIFIED FOR THE DYNAMIC SQL; STATEMENT BEING PROCESSED IS NOT VALID
I had gone through ibm knowledge center and found this page.
I understand db2 allows 3 forms of insert:
There are three forms of this statement:
The INSERT via VALUES form is used to insert a single row into the table or view using the values provided or referenced.
The INSERT via SELECT form is used to insert one or more rows into the table or view using values from other tables, or views, or both.
The INSERT via FOR n ROWS form is used to insert multiple rows into the table or view using values provided or referenced.
My question is why db2 is looking for "for n rows" clause in my query.
Note: this query is being sent through SSGODBC.
Might want to try and explicitly state the columns.
INSERT INTO Schema1.table1 (col1,col2,...) SELECT col1,col2,... FROM Schema2.table2

How can I INSERT data into two tables simultaneously with only one sql script db2?

How would I insert into multiple tables with one sql script in db2
For example, insert a row into T1 DOCK_DOOR and then insert into T2 DOCK_DOOR_LANE multiple times based on the dock_door_sysid from the first table.
My first approach was the following. I was attempting to use a with with three inserts. on the other hand, doing to inserts on the second table is not and option if this can be automated with one insert.
thanks for any feedback
sql example
WITH ins AS (
INSERT INTO DBF1.DOCK_DOOR (DOCK_DOOR_SYSID,DOOR_NUMBER,DOOR_NAME,DOCK_SYSID,DOOR_SEQ,ENCRYPTION_CODE,RFID_ENBLD_FLAG,LANES_COUNT,CMNT_TEXT,CREATE_TS,CREATE_USERID,UPDATE_TS,UPDATE_USERID,VER_NUMBER,ACTIVE_FLAG,STATUS_SYSID,DOOR_TYPE_SYSID)
VALUES (nextval for DBF1.DOCK_DOOR_SEQ,'026','DOOR025',61,25,NULL,'N','2',NULL,current timestamp,'SQL_INSERT',current timestamp,'SQL_INSERT',0,NULL,1723,1142)
RETURNING door_number,dock_door_sysid),
ins2 AS (
INSERT INTO SIT.DOCK_DOOR_lane (DOCK_DOOR_LANE_SYSID,DOOR_LANE_ID,DOCK_DOOR_SYSID,LANE_ID,CREATE_TS,CREATE_USERID,UPDATE_TS,UPDATE_USERID,VER_NUMBER)
VALUES (nextval for DBF1.DOCK_DOOR_LANE_seq,door_number||''||'A',dock_door_sysid,'A',current timestamp},'SQL_INSERT',current timestamp,'SQL_INSERT',0)
SELECT door_number,dock_door_sysid FROM DBF1.DOCK_DOOR
RETURNING door_number,dock_door_sysid)
INSERT INTO DBF1.DOCK_DOOR_lane (DOCK_DOOR_LANE_SYSID,DOOR_LANE_ID,DOCK_DOOR_SYSID,LANE_ID,CREATE_TS,CREATE_USERID,UPDATE_TS,UPDATE_USERID,VER_NUMBER)
VALUES (nextval for DBF1.DOCK_DOOR_LANE_seq,door_number||''||'B',dock_door_sysid,'B',current timestamp},'SQL_INSERT',current timestamp,'SQL_INSERT',0)
SELECT door_number,dock_door_sysid FROM DBF1.DOCK_DOOR;
Table 1 = dock_door
Table 2 = Dock_door_lane
You could do it with a trigger on the dock_door table.
However, if you're on a recent, version on IBM i. You might be able to make use of data change table reference
Your statement would look something like this
insert into dock_door_lane
select <....>
from final table (insert into dock_door <...>)
I'm not sure it will work, as this article indicates that at least at a couple of years ago DB2 for i didn't support the secondary insert required.
This old SO question also seems to confirm that at least at v7.1, the double insert isn't supported.
If I get a chance, I'll run a test on a 7.2 system Monday.

How does insert into select work internally in SQL Server?

Let's consider the following insertion:
INSERT INTO SOMETABLE
SELECT * FROM SOMETABLE
WHERE Column > NUMBER
Is there a risk that result set of the SELECT statement can be changed due to inserting?
In the other words how many times the SELECT statement can be calculated by query engine to perform INSERT INTO SELECT to the same table?
Assumption: A single thread scenario without concurrent transactions.
Is there a risk that result set of the SELECT statement can be changed due to inserting?
No. The result set of the SELECT statement will not be affected by the INSERT. The result of the SELECT will be the same as if you ran it by itself.

Difference between INSERT INTO and INSERT ALL INTO

While I was inserting some records in table i found that..
INSERT INTO T_CANDYBAR_DATA
SELECT CONSUMER_ID,CANDYBAR_NAME,SURVEY_YEAR,GENDER,1 AS STAT_TYPE,OVERALL_RATING
FROM CANDYBAR_CONSUMPTION_DATA
UNION
SELECT CONSUMER_ID,CANDYBAR_NAME,SURVEY_YEAR,GENDER,2 AS STAT_TYPE,NUMBER_BARS_CONSUMED
FROM CANDYBAR_CONSUMPTION_DATA;
79 rows inserted.
INSERT ALL
INTO t_candybar_data VALUES (consumer_id,candybar_name,survey_year,gender,1,overall_rating)
INTO t_candybar_data VALUES (consumer_id,candybar_name,survey_year,gender,2,number_bars_consumed)
SELECT * FROM candybar_consumption_data
86 rows inserted.
I have read somewhere that INSERT ALL INTO automatically unions then why those difference is showing.
The problem is your queries are different—your first is with UNION and your second is without—so they are naturally inserting different numbers of values. As far as what INSERT ALL is versus a straight INSERT:
INSERT can be used for inserting new records to a single table.
INSERT ALL can be used for inserting new records to multiple tables based on the query condition.
So your assumption as stated here:
I have read somewhere that INSERT ALL INTO automatically unions then
why those difference is showing.
Is incorrect. INSERT ALL doesn’t have anything to do with UNION in any way. But that said, you might be mixing up UNION ALL as explained here.
The SQL UNION ALL operator is used to combine the result sets of 2 or
more SELECT statements. It returns all rows from the query (even if
the row exists in more than one of the SELECT statements).
Each SELECT statement within the UNION ALL must have the same number
of fields in the result sets with similar data types.

Insert Multiple Rows into Table from a Table

I have a SQL Server 2008 database. The database has a stored procedure which receives two strings as parameters. One parameter is used to build a temp table which will usually only have 1 or 2 rows but theoretically could have more.
For each row in the temp table, I need to insert a row into a different table that consists of the other parameter and the contents of the temp table. Is there a way to do this without a cursor?
I've tried variations on the following:
Pseudo code:
procedure InsertLinks(#Key varchar(36), #LinkKey varchar(36)
tempLinks Table = getLinks(#LinkKey)
Insert into MyTable (Key, LinksTo) Values (#Key, Select LinksTo From tempLinks)
The VALUES clause is messed up - you have a single value comma a table. That's not valid.
The following should work just fine:
INSERT INTO MyTable (Key, LinksTo)
SELECT #Key, LinksTo
FROM tempLinks