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What is the recommended way to delete a large number of items from DynamoDB?
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What I ideally want to do is call LogTable.DeleteItem(user_id) -
Without supplying the range, and have it delete everything for me.
An understandable request indeed; I can imagine advanced operations like these might get added over time by the AWS team (they...
Create unique constraint with null columns
I have a table with this layout:
4 Answers
4
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How can i query for null values in entity framework?
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Workaround for Linq-to-SQL:
var result = from entry in table
where entry.something.Equals(value)
select entry;
Workaround for Linq-to-Entities (ouch!):
var result = from entry in table
where (value == null ? entry.something == null : entr...
How to think in data stores instead of databases?
...trained my mind to think 100% in object relationships that map directly to table structures, and now it's hard to see anything differently. I can understand some of the benefits of Google Datastore (e.g. performance and the ability to distribute data), but some good database functionality is sacrif...
How to change a table name using an SQL query?
How can I in change the table name using a query statement?
10 Answers
10
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Most Pythonic way to provide global configuration variables in config.py? [closed]
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"mysql": {
"user": "root",
"pass": "secret",
"tables": {
"users": "tb_users"
}
# etc
}
}
You'd access the values as follows:
config["mysql"]["tables"]["users"]
If you are willing to sacrifice the potential to compute expressions ins...
Mocking python function based on input arguments
...om a database and we would like to test this module by mocking pd.read_sql_table method (which takes table_name as argument).
What you can do is to create (inside your test) a db_mock method that returns different objects depending on the argument provided:
def db_mock(**kwargs):
if kwargs['ta...
#1071 - Specified key was too long; max key length is 1000 bytes
... was too long; max key length is 3072 bytes' when ran this script:
CREATE TABLE IF NOT EXISTS test_table1 (
column1 varchar(500) NOT NULL,
column2 varchar(500) NOT NULL,
column3 varchar(500) NOT NULL,
column4 varchar(500) NOT NULL,
column5 varchar(500) NOT NULL,
column6 varchar(500) NOT...
搭建高可用mongodb集群（四）—— 分片 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...需要分片的集合和片键
db.runCommand( { shardcollection : "testdb.table1",key : {id: 1} } )
我们设置testdb的 table1 表需要分片，根据 id 自动分片到 shard1 ，shard2，shard3 上面去。要这样设置是因为不是所有mongodb 的数据库和表 都需要分片！
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On delete cascade with doctrine2
... make a simple example in order to learn how to delete a row from a parent table and automatically delete the matching rows in the child table using Doctrine2.
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