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Disabling contextual LOB creation as createClob() method threw error
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Basically here we are simply checking
whether we can call the
java.sql.Connection methods for LOB
creation added in JDBC 4. We not only
check whether the java.sql.Connection
declares these methods, but also
whether the actual java.sql.Connection
instance implements them (i.e. can b...
Counting null and non-null values in a single query
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This works for Oracle and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) from us...
柳青：滴滴每天面临向死而生的挑战 永远热泪盈眶 - 资讯 - 清泛网 - 专注C/...
...家看看那一排是我们的高层管理者，其实他们都很年轻，包括James也是一张年轻的脸，每个深身上都有很独特的青春气息，这是非常难得的，这种就是年轻，就是热血。不知道有多少同学刚刚加入滴滴半年的时间，恭喜你们，你...
Only initializers, entity members, and entity navigation properties are supported
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Entity is trying to convert your Paid property to SQL and can't because it's not part of the table schema.
What you can do is let Entity query the table with no Paid filter and then filter out the not Paid ones.
public ActionResult Index()
{
var debts = storeDB.Orders...
What are best practices for multi-language database design? [closed]
...lly you should develop your own database access class, that pre-parses the SQL that contains your special localization markup and converts it to the actual SQL you will need to send to the database.
Using that system might look something like this:
db.setLocale("en");
db.query("SELECT p.price, _(p...
How to store arrays in MySQL?
I have two tables in MySQL. Table Person has the following columns:
7 Answers
7
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Convert Linq Query Result to Dictionary
I want to add some rows to a database using Linq to SQL, but I want to make a "custom check" before adding the rows to know if I must add, replace or ignore the incomming rows.
I'd like to keep the trafic between the client and the DB server as low as possible and minimize the number of queries.
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CHECK constraint in MySQL is not working
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MySQL 8.0.16 is the first version that supports CHECK constraints.
Read https://dev.mysql.com/doc/refman/8.0/en/create-table-check-constraints.html
If you use MySQL 8.0.15 or earlier, the MySQL Reference Manual says:
The...
Update multiple rows in same query using PostgreSQL
I'm looking to update multiple rows in PostgreSQL in one statement. Is there a way to do something like the following?
6 An...
Convert MySQL to SQlite [closed]
Is it possible to convert from MySQL to SQLite with a free tool on windows?
15 Answers
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