大约有 9,000 项符合查询结果（耗时：0.0184秒） [XML]
Create table (structure) from existing table
...
Worked for me in MSSQL 2008 R2
– Pyrite
Mar 29 '17 at 14:28
1
...
When should I use UNSIGNED and SIGNED INT in MySQL?
When should I use UNSIGNED and SIGNED INT in MySQL ?
What is better to use or this is just personal prefernce ?
Because I've seen it used like this;
...
What are the advantages of using a schema-free database like MongoDB compared to a relational databa
I'm used to using relational databases like MySQL or PostgreSQL, and combined with MVC frameworks such as Symfony, RoR or Django, and I think it works great.
...
How do I interpret precision and scale of a number in a database?
...
Note that MS SQL Server wouldn't allow 12345 or 1234.56 because "[scale] is substracted from [precision] to determine the maximum number of digits to the left of the decimal point." (source: decimal and numeric)
– mo...
全食超市（Whole Foods Market）——精品超市的运营之道 - 资讯 - 清泛网 -...
...要求来自于生态良好的有机农业生产体系生产和加工，不使用化学农药、化肥、化学防腐剂等合成物质。有机动物产品则表示其在饲养过程中采用100%有机饲料，没有被使用过促生长激素或抗生素，并且有充足的户外活动空间。...
How to drop unique in MySQL?
...
Simply you can use the following SQL Script to delete the index in MySQL:
alter table fuinfo drop index email;
share
|
improve this answer
|
...
MIN/MAX vs ORDER BY and LIMIT
... faster in the worst case, indistinguishable in the best case, is standard SQL and most clearly expresses the value you're trying to get. The only case where it seems that using SORT and LIMIT would be desirable would be, as mson mentioned, where you're writing a general operation that finds the to...
API pagination best practices
...just an incrementing number and does not preserve a date or a time. ... In SQL server 2008 and later, the timestamp type has been renamed to rowversion, presumably to better reflect its purpose and value." So there's no evidence here that timestamps (those that actually contain a time value) are uni...
MongoDB vs. Cassandra [closed]
...mentation; Cassandra provides native Hadoop support, including for Hive (a SQL data warehouse built on Hadoop map/reduce) and Pig (a Hadoop-specific analysis language that many think is a better fit for map/reduce workloads than SQL). Cassandra also supports use of Spark.
Not worried about "massiv...
Using current time in UTC as default value in PostgreSQL
...
FWIW, running this query in PostgreSQL 11.5: ALTER TABLE testcase_result ADD COLUMN date_created TIMESTAMP WITHOUT TIME ZONE DEFAULT (NOW() AT TIME ZONE "UTC") NOT NULL; fails with: ERROR: column "UTC" does not exist. Make sure 'utc' is all lower-case.
...