is a very powerful feature of MyBatis. It enables programmers have to write the 
.  MyBatis uses a powerful Dynamic 
 statement. Following are the OGNL based Dynamic 
 expressions provided when, otherwise  trim where, set  foreach  The if Statement  The most common thing to do in dynamic 
 is conditionally include a part of a where clause. For example −  
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 © 2018 Percona.   1  Peter Zaitsev  Using MySQL for Distributed  Database Architectures  CEO, Percona PingCAP Infra Meetup,  Shanghai, China, May 26, 2018  © 2018 Percona.   2  About Percona  Solutions enterprises  © 2018 Percona.   3  Presentation  Cover Basics   Why Going Distributed   How to do it   © 2018 Percona.   4  Distributed  ?  MySQL Deployment on More  than one System  © 2018 Percona.   5  Modern Active Users Possible  15M of Daily Active Users counting time of day skew  © 2018 Percona.   8  Distributed  Systems Tend To be   More Complicated to Develop Against   More Complicated to Operate   Have 
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  C++20 ❤ SQL 
John R Bandela, MDOverview
u
SQL 
u
C++ Example
u
Implementation techniques
u fixed_string
u meta_struct
u Parsing compile time strings into meta_structsOverview
v
SQL 
v
C++ Example “CppCon”Query  for orders with input from user 
SELECT orders.id, name, item, price, discount_code
FROM orders JOIN customers ON customers.id = customerid
WHERE price > {price_from_user};Avoiding SQL  Injection item, price, discount_code
FROM orders JOIN customers ON customers.id = customerid
WHERE price > ?;SQL  Library Options
u
Traditional database library with strings
u
Domain specific language
u
Object
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  Updates to a shared chat / drawing canvas – Game events  © Joe Mertz – Mobile to Cloud: Building Distributed  Applications  • Workarounds have been devised • E.g. Polling  – Client continuously polls the server stamp for   the next time he wants to send a letter.  © Joe Mertz – Mobile to Cloud: Building Distributed  Applications  • Provides for true two-way ongoing communication   between a client and server. Note:  – Some old browsers don't implement WebSockets  © Joe Mertz – Mobile to Cloud: Building Distributed  Applications  // Create a new WebSocket var wSocket = new WebSocket("ws://www.example.com/socketserver")
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  program for a supercomputer?
Introduce PGAS Model, RDMA
Building Remote Pointer Types
Building Distributed  Data Structures
Extending to GPUsThis Talk
Background: how do we write a program for a supercomputer supercomputer?
Introduce PGAS Model, RDMA
Building Remote Pointer Types
Building Distributed  Data Structures
Extending to GPUsThis Talk
Background: how do we write a program for a supercomputer?
Introduce Introduce PGAS Model, RDMA
Building Remote Pointer Types
Building Distributed  Data Structures
Extending to GPUsThis Talk
Background: how do we write a program for a supercomputer?
Introduce PGAS Model
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  Firebird Null Guide  NULL behaviour and pitfalls in Firebird SQL   Paul Vinkenoog  Version 1.2, 30 June 2020  Table of Contents  1. What is NULL? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4  2. NULL support in Firebird SQL  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  operations will render the entire expression NULL.  This guide explores the behaviour of NULL in Firebird SQL , points out common pitfalls and shows  you how to deal safely with expressions that contain NULL or
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  TiDB: HBase分布式事务与SQL 实现  About me  ● TiDB & Codis founder  ● Golang expert  ● Distributed  database developer  ● Currentlly, CEO and co-founder of PingCAP  liuqi@pingcap.com        https://github.com/pingcap/tidb Bloom Filters for real-time queries.  ● Query  predicate push down via server side Filters  ● MVCC  What did they say ?  “Nothing is hotter than SQL -on-Hadoop, and now SQL -on- HBase is fast approaching equal hotness status”           Form HBaseCon 2015  We want more !             SQL  + Transaction(ACID)  TiDB  Features  ● Consistent distributed  transactions   ○ TiDB makes your application code simple and robust
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  第三届中国Rust开发者⼤会  ⽤ egg 孵化你的 SQL  优化器  王润基   RisingWave 内核开发⼯程师 ?  Parser  Binder  Optimizer  Executor  SQL   AST  Logical Plan  Physical Plan Table  Catalog Storage  RisingLight 查询引擎的整体结构  SELECT name, url url  FROM t1 JOIN t2  WHERE t1.id = t2.id    AND name = ‘Bob’  SQL  Logical Plan Physical Plan  Projection  name, url  Filter   t1.id = t2.id  name = “Bob”  Join  Scan   t1(id, name)  Scan   t2(id, url) Filter   #1 = “Bob”  Hash Join   #0 = #2  Scan   $1.1, $1.2  Scan   $2.1, $2.2  Projection   #1, #3  ⼀个 SQL  语句优化的例⼦  基于规则的优化 (RBO) 基于代价的优化 (CBO)  谓词下推  Join  Filter  A B  Join  Filter  A B  Filter  Join  A Join
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