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SQL statement to get column type
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Using SQL Server:
SELECT DATA_TYPE
FROM INFORMATION_SCHEMA.COLUMNS
WHERE
TABLE_NAME = 'yourTableName' AND
COLUMN_NAME = 'yourColumnName'
share
|...
How to work with Git branches and Rails migrations
...'On branch ','').chomp
%>
defaults: &defaults
pool: 5
adapter: mysql2
encoding: utf8
reconnect: false
username: root
password:
host: localhost
<% environments.each do |environment| %>
<%= environment %>:
<<: *defaults
database: <%= [ database_prefix...
How to solve “Fatal error: Class 'MySQLi' not found”?
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Sounds like you just need to install MySQLi.
If you think you've done that and still have a problem, please post your operating system and anything else that might help diagnose it further.
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Calculate difference between two datetimes in MySQL
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USE TIMESTAMPDIFF MySQL function. For example, you can use:
SELECT TIMESTAMPDIFF(SECOND, '2012-06-06 13:13:55', '2012-06-06 15:20:18')
In your case, the third parameter of TIMSTAMPDIFF function would be the current login time (NOW()). Second parameter would be the last login time, w...
AI2Utils 拓展：一些常用的小功能集合 · App Inventor 2 中文网
... 事件
方法
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是否首次运行、重置首次运行、返回桌面、打开系统设置、打开网络设置已并入原生组件应用工具。新项目无需导入拓展；旧版 AIX 下载仍保留（通讯录查询仍在拓展内）。
AI2Ut...
Select last N rows from MySQL
I want to select last 50 rows from MySQL database within column named id which is primary key . Goal is that the rows should be sorted by id in ASC order, that’s why this query isn’t working
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How can I add comments in MySQL?
...es of commenting are supported
Hash base single line commenting using #
Select * from users ; # this will list users
Double Dash commenting using --
Select * from users ; -- this will list users
Note : Its important to have single white space just after --
3) Multi line commenting using ...
ElasticSearch, Sphinx, Lucene, Solr, Xapian. Which fits for which usage? [closed]
... SET NAMES utf8
# query before fetching rows to index
sql_query = SELECT *, id AS pid, CRC32(safetag) as safetag_crc32 FROM hb_posts
sql_attr_uint = pid
# pid (as 'sql_attr_uint') is necessary for sphinx
# this field must be unique
# that is why I like sphinx
# you ...
UPDATE multiple tables in MySQL using LEFT JOIN
...= t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
FROM t2
)
See the article in my blog for performance details...
MySQL - why not index every field?
...k about index updates were one update trigger all indexes update this is a select all unordered equivalent in time
from this I conclude that you have in this scenario that if you will loose this time is preferable to lose it in a select nor an update because if you will select a field that is not i...