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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
In PostgreSQL I have a table with a varchar column. The data is supposed to be integers and I need it in integer type in a query. Some values are empty strings.
The following:
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Migration: Cannot add foreign key constraint
I'm trying to create foreign keys in Laravel however when I migrate my table using artisan i am thrown the following error:
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How can I export the schema of a database in PostgreSQL?
...ed formats
--lock-wait-timeout=TIMEOUT fail after waiting TIMEOUT for a table lock
-?, --help show this help, then exit
Options controlling the output content:
-a, --data-only dump only the data, not the schema
-b, --blobs include large objec...
Read specific columns from a csv file with csv module?
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I think Pandas is a perfectly acceptable solution. I use Pandas often and really like the library, but this question specifically referenced the CSV module.
– frankV
May 23 '17 at 17:05
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COUNT DISTINCT with CONDITIONS
...tinct items in a column subject to a certain condition, for example if the table is like this:
5 Answers
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MySQL “WITH” clause
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Update: MySQL 8.0 is finally getting the feature of common table expressions, including recursive CTEs.
Here's a blog announcing it: http://mysqlserverteam.com/mysql-8-0-labs-recursive-common-table-expressions-in-mysql-ctes/
Below is my earlier answer, which I originally wrote in 200...
SQL update from one Table to another based on a ID match
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You might want to use the table alias in the UPDATE clause, otherwise it will cause problems if you self join the table at any point.
– Tom H
Oct 22 '08 at 20:38
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When do I need to use a semicolon vs a slash in Oracle SQL?
....2.0.1.0 - Production
With the Partitioning and OLAP options
SQL> drop table foo;
Table dropped.
SQL> /
drop table foo
*
ERROR at line 1:
ORA-00942: table or view does not exist
In this case one actually notices the error.
But assuming there is a SQL script like this:
drop...
SQL variable to hold list of integers
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Table variable
declare @listOfIDs table (id int);
insert @listOfIDs(id) values(1),(2),(3);
select *
from TabA
where TabA.ID in (select id from @listOfIDs)
or
declare @listOfIDs varchar(1000);
SET @listOfIDs = ',1,2,3...
Postgres: How to do Composite keys?
... error, and omit the redundant CONSTRAINT (already implied), too:
CREATE TABLE tags
(
question_id INTEGER NOT NULL,
tag_id SERIAL NOT NULL,
tag1 VARCHAR(20),
tag2 VARCHAR(20),
tag3 VARCHAR(20),
PRIMARY ...