Questions tagged [cast]
Converts an expression of one data type to another.
131
questions
0
votes
1
answer
119
views
What is the idiomatic way to truncate a string down to 100 byte-pairs?
nvarchar(100) holds 100 byte-pairs, as documented here. LEFT([Your String], 100) truncates your string down to 100 characters as documented here. These are not the same.
Foolishly, I have used LEFT([...
- 545
4
votes
1
answer
294
views
Postgres strange conversion of the string 'now' to timestamp
It looks like postgres treats the string 'now()' the same as a call to the now() function.
Why does postgres allow this?
select 'now'::timestamp;
or this?
select 'now()'::timestamp;
or even this?
...
- 143
1
vote
1
answer
818
views
PostgreSQL 15: ERROR: operator is not unique: unknown || double precision
we are using a PostgreSQL version 15 and have added 13 conversions from this blog entry:
http://petereisentraut.blogspot.com/2008/03/readding-implicit-casts-in-postgresql.html
However, only now we ...
- 21
1
vote
1
answer
23
views
How can I sort by "release" in Mysql, where e.g. 10.10 comes after 10.9, with non-numerical entries both before and after?
If I have a table as per https://www.db-fiddle.com/f/arPEdUty3U6AJEQfqYEyRc/1 with a list of releases:
INSERT INTO `releases` (`ReleaseID`, `ReleaseNumber`) VALUES
(1, '10.6'),
(2, '10.8'),
(3, '_TBD')...
- 173
2
votes
2
answers
2k
views
XML datatype instance has too many levels of nested nodes. Maximum allowed depth is 128 levels
This is the error message I get when running the query below:
Msg 6335, Level 16, State 102, Line 43 XML datatype instance has too
many levels of nested nodes. Maximum allowed depth is 128 levels.
...
- 16.3k
0
votes
0
answers
18
views
Combine INT, TIME fields and compute Elapsed Percentage
Need calculation and conversion help...
Columns:
[Days] INT
[hh:mm:ss] Time
[AllowedRuntimeMinutes] INT
Need to combine [Days]+[hh:mm:ss] as the duration the query has been running, and then calculate ...
- 33
3
votes
1
answer
889
views
In Snowflake, how do I CAST CURRENT_TIMESTAMP up to the minute only?
In Snowflake, how do I CAST CURRENT_TIMESTAMP up to the minute only. I don't want seconds, milliseconds, or timezone included in my result.
- 65
1
vote
0
answers
803
views
Convert Integer Array to JSON Array
I'm not sure how I should go about converting int[] to json[], here's what I've tried so far:
db=# alter table product alter column images type json[] using images::json[];
ERROR: cannot cast type ...
- 111
2
votes
1
answer
1k
views
How can I utilize an index with a different type or collation in a LEFT JOIN in MySQL?
I am trying to debug a slow query, and when I EXPLAIN the SQL, I get a warning:
Warning: #1739 Cannot use ref access on index '[index name]' due to type or collation conversion on field '[field name]' ...
- 173
0
votes
2
answers
3k
views
Convert hex string representation to hex number in SQL Server T-SQL
I have been given a dataset where hexadecimal numbers have been stored as a quasi-hex string representation intended to be human-friendly, e.g. "16A1". Is there a conversion function in T-...
- 545
0
votes
1
answer
135
views
Why isn't it trivial to create a virtual integer timestamp column from a TIMESTAMP column in MySQL?
There's no way to extract an integer timestamp from a TIMESTAMP column in a virtual column context in MySQL because UNIX_TIMESTAMP is not allowed in virtual columns. Why isn't this a trivial task?
- 235
0
votes
2
answers
258
views
Can I create a cast from a composite (table or row) type to a domain?
Let's say I have a simple table foo, and domain bar
CREATE TABLE foo(x)
AS VALUES (1),(2),(3);
CREATE DOMAIN bar AS text;
Is it possible to make a cast such that I can do
SELECT foo::bar FROM foo;
...
- 63.9k
2
votes
1
answer
406
views
How to copy data between postgres schemas if there are objects?
I removed shop from database, that should not be removed. Fortunately I had backup and reverted this backup to schema public_backup.
Now I am trying to restore only this shop. I can't override my ...
- 209
1
vote
1
answer
525
views
Best way to cast a VIEW row type to the underlying TABLE row type
I have a table with an index and a row-level security policy. Due to this problem (more details: 1, 2, 3, 4, 5), the index is not used when the policy applies, which makes my queries unbearably slow.
...
- 514
3
votes
1
answer
644
views
I can't understand a syntax error issue in SQL / TimeScaleDB
This does NOT compile:
SELECT add_compression_policy(
hypertable => 'exchange.candles',
compress_after => INTERVAL ((SELECT now()::DATE::timestamp - (SELECT min(last_ts) FROM exchange....
- 303