2,805 questions
0
votes
1
answer
85
views
How to pass fieldnames containing # to createMultipleInsertCommand without crashing?
We have this code which works well most of the time, except for a case I will describe slightly latter:
/**
* Recovers archived survey responses
*
* @param int $surveyId survey ID
* @param string $...
- 81.4k
0
votes
2
answers
226
views
Spring Data JPA, use GROUP BY to return a list of rows grouped by a column
@Entity
public class Employee {
@Id
@GeneratedValue
private long id;
private String name;
private String dept;
private long salary;
.............
}
I am trying to get the result of ...
- 6,298
0
votes
2
answers
127
views
Why does DDL use Interpreter and DML use compiler?
I am currently doing DBMS course. While studying DDL and DML I came to realize that DDL use Interpreter and DML use compiler. Interpreter execute codes line by line and Compiler executes whole code at ...
-1
votes
1
answer
122
views
MySQL B-Tree Index on a Numeric Value in a VARCHAR Column - Inefficiency Concerns
im working with a MySQL database where I have a column of type VARCHAR, but it stores numeric values. I created a B-Tree index on this column to optimize queries like:
E.x > n
n < E.x
n = E.x
(...
-4
votes
1
answer
82
views
What design shows parent id and child-specific data in the same table without violating normalization? [closed]
I am designing a system that records stock transactions for a product. Some product types record items by serial number for traceability, some products types do not serialize items.
I record the ...
- 79
0
votes
0
answers
71
views
Is there any migration mechanism for altering table schema in Ibis?
We are planning to shift from infi.clickhouse to ibis, so I was wondering, does ibis support the migration of old schema to new like infi.clickhouse?
If not, then what could be the solution to this?
...
- 15
2
votes
2
answers
189
views
Change to Postgres indexing scheme for IS NOT NULL?
I have a Postgres table that has numerous columns which frequently show up in the where clause of select queries. The table has been indexed accordingly, with indexes on all of these columns (mostly ...
0
votes
1
answer
49
views
Optimizing retry intervals for fetching transaction status from a payment gateway
I have a system where transactions are initially marked as "Pending" in a relational database, if a payment transaction is not immediately successful by payment gateway, I need to fetch the ...
1
vote
1
answer
63
views
large offset limit taking time
My OrientDB 3.2 application can have millions of vertices and edges. The query below fetches the records from superclass V.
select FROM `V`
where class_name = ['Database', 'Table'] AND is_asset_class !...
- 11
0
votes
1
answer
2k
views
Snowflake error, Unsupported subquery type cannot be evaluated
I have a user defined function which returns number, argument is also a number. There is an aggregate function(sum()) inside the UDF. I am calling this UDF from a select clause. It's giving me the ...
- 348
-1
votes
1
answer
52
views
Combine SQL queries for output
I have two queries, where I need to get the ID from the first query and pass it to the second query.
How do I do this for all the ID's in the first query?
select id, name from [ignite].[COND] --> ...
- 333
1
vote
1
answer
113
views
Does Cassandra offer any semantics similar to REPEATABLE READ?
Does Cassandra offer any semantics similar to REPEATABLE READ?
I believe you can do this within a "batched" LWT, but doesn't this incur significant network overhead due to PAXOS? REPEATABLE ...
- 439
0
votes
1
answer
60
views
How can I get a duplicate key error if the row does not match the predicate of the unique index?
I'm using Postgres v16. I've got a unique index on my invoice table:
CREATE UNIQUE INDEX unq_invoice_display_id
ON invoice (tenant_id, display_id, expiry_timestamp)
WHERE id = original_invoice_id;
#...
- 2,001
1
vote
1
answer
283
views
How drop unused column with dbms_redefinition in Oracle database?
I don't really understand how to delete columns using the dbms_redefinition utility. All the time there are some strange errors and data overwriting. Disabled foreign keys appear in other tables and ...
- 228
-4
votes
2
answers
147
views
Why should the operands for UNION be SELECT statements and not tables?
In SQL, given tables T and S that have the same schema, say,
CREATE TABLE "T" ("ID" INTEGER, "Salary" REAL);
CREATE TABLE "S" ("ID" INTEGER, "...
- 14