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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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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...
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...
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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#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...
How do I use cascade delete with SQL Server?
I have 2 tables: T1 and T2, they are existing tables with data. We have a one to many relationship between T1 and T2. How do I alter the table definitions to perform cascading delete in SQL Server when a record from T1 is deleted, all associated records in T2 also deleted.
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