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What is Scala's yield?
...ndrum - Which interestingly enough is the same order in which the original SQL spec outlines. Somewhere along the way the SQL language inverted the order, but it makes complete sense to first describe what you are pulling from followed by what you expect to get out of it.
– Jo...
Get generated id after insert
I'm using the SQLite with Android, and I want to know the best way to get the generated id of the row I inserted.
5 Answers...
How big is too big for a PostgreSQL table?
...,1 as c2,2 as c3
from generate_series(1,90000000) x;
https://wiki.postgresql.org/wiki/FAQ
Limit Value
Maximum Database Size Unlimited
Maximum Table Size 32 TB
Maximum Row Size 1.6 TB
Maximum Field Size 1 GB
Maximum Rows per Table Unlimited
Maximum Columns...
Examples of GoF Design Patterns in Java's core libraries
...nd - TextComponent's Undo/Redo.
Interpreter - RegEx (java.util.regex.) and SQL (java.sql.) API.
Prototype - Not 100% sure if this count, but I thinkg clone() method can be used for this purpose.
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What is causing ERROR: there is no unique constraint matching given keys for referenced table?
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In postgresql all foreign keys must reference a unique key in the parent table, so in your bar table you must have a unique (name) index.
See also http://www.postgresql.org/docs/9.1/static/ddl-constraints.html#DDL-CONSTRAINTS-FK and s...
How to add a line break in C# .NET documentation
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/// <summary>
/// <para>Get a human-readable variant of the SQL WHERE statement of the search element.</para>
/// Rather than return SQL, this method returns a string with icon-tokens, which
/// could be used to represent the search in a condensed pictogram format.
/// </sum...
PHP function to build query string from array
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Implode will combine an array into a string for you, but to make an SQL query out a kay/value pair you'll have to write your own function.
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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
...个TDDL，是taobao的一个数据访问层组件，他主要的作用是SQL解析、路由处理。根据应用的请求的功能解析当前访问的sql判断是在哪个业务数据库、哪个表访问查询并返回数据结果。具体如图：
说了这么多传统数据库的架构，那N...
Hibernate Annotations - Which is better, field or property access?
...a is to shy away from ORM solutions altogether. Learn how to write proper SQL.
– duffymo
May 27 '16 at 16:44
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JPA EntityManager: Why use persist() over merge()?
...ached, entityToSave);
return attached;
}
Although if connected to MySQL merge() could be as efficient as persist() using a call to INSERT with ON DUPLICATE KEY UPDATE option, JPA is a very high level programming and you can't assume this is going to be the case everywhere.
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