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How to prevent Node.js from exiting while waiting for a callback?
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I did look at felixge/node-mysql library and didn't see a reference to the command client.connect in the API. Is this the actual call you're trying to make (not trying to be nitpicky here)? Regardless, IMHO you need to think more about how Javascript...
Excel to CSV with UTF8 encoding [closed]
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Needed to export an XLS as CSV to import in MySQL. Using Excel 2003 I exported in format "Unicode Text (.txt)", then used Notepad++ to replace the TAB with ;, then imported the txt-file into phpmyadmin with default "Character set of the file: utf-8", Format "CSV using ...
Laravel orderBy on a relationship
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If you use mysql strict mode, which is default in Laravel 5.4 ,f.ex you'll receive SQLSTATE[42000]: Syntax error or access violation: 1140 Mixing of GROUP columns ...
– Sabine
Feb 18 '17 at 15:15
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Computed / calculated / virtual / derived columns in PostgreSQL
...s defined in the SQL standard and implemented by some RDBMS including DB2, MySQL and Oracle. Nor the similar "computed columns" of SQL Server.
STORED generated columns are introduced with Postgres 12. Trivial example:
CREATE TABLE tbl (
int1 int
, int2 int
, product bigint GENERATED ALWAYS...
Why should I use document based database instead of relational database?
... my schema, I am constantly frustrated by having to maintain the schema in MySQL/SQLite. While I've not done too much with CouchDB yet, I do like how simple it is to evolve the schema during the RAD process.
A case where you might not want to use a non-relational database is when you have a lot of ...
SQLAlchemy: how to filter date field?
..., once it's DateTime or timestamp - it's usually finished with 00:00 (both MySQL & PostgreSQL do this). More generic solution is not to cast, but to set the date you are sending to it's .endOfDay() so you actually send 1988-01-17 23:59:59 to the database compare :)
– jave.w...
Difference between CLOB and BLOB from DB2 and Oracle Perspective?
...es, documents, other)
CLOB is for large text data (text)
Maximum size on MySQL 2GB
Maximum size on Oracle 128TB
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从源代码剖析Mahout推荐引擎 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
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通过“策略模式”匹配不同的数据源，支持File, JDBC(MySQL, PostgreSQL), NoSQL(Cassandra, HBase, MongoDB)。
注：NoSQL的实现在mahout-integration-0.8.jar中。
数据格式支持2种：
GenericDataModel: 用户ID，物品ID，用户对物品的打分(UserID,ItemID,Pre...
HTTP authentication logout via PHP
...cookie, with the persistence of state stored on the server in some manner (mysql, sqlite, flatfile, etc). This will require all requests to be evaluated, for instance, with PHP.
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What is the Oracle equivalent of SQL Server's IsNull() function?
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+1: COALESCE is ANSI, supported by Postgres, MySQL... The only caveat is that it doesn't necessarily perform as fast as native syntax.
– OMG Ponies
Aug 19 '10 at 17:33
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