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How to add where condition to sql with JSqlParser?

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问题 I want to add where condition to sql with JSqlParser, for example: Before: select * from test_table where a=1 group by c After: select * from test_table where a=1 and b=2 group by c However, I cannot find any example codes. 回答1: One solution would be: String sql = "select * from test_table where a=1 group by c"; Select select = (Select) CCJSqlParserUtil.parse(sql); Expression where = CCJSqlParserUtil.parseCondExpression("a=1 and b=2"); ((PlainSelect) select.getSelectBody()).setWhere(where);

How to add where condition to sql with JSqlParser?

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PageHelper分页插件的原理是什么

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作者：祖大俊原文： https: / /my.oschina.net/zudajun /blog/ 745232 PageHelper是一款好用的开源免费的Mybatis第三方物理分页插件，其实我并不想加上好用两个字，但是为了表扬插件作者开源免费的崇高精神，我毫不犹豫的加上了好用一词作为赞美。原本以为分页插件，应该是很简单的，然而PageHelper比我想象的要复杂许多，它做的很强大，也很彻底，强大到使用者可能并不需要这么多功能，彻底到一参可以两用。但是，我认为，作为分页插件，完成物理分页任务是根本，其它的很多智能并不是必要的，保持它够傻够憨，专业术语叫stupid，简单就是美。我们将简单介绍PageHelper的基本使用和配置参数的含义，重点分析PageHelper作为Mybatis分页插件的实现原理。 1. PageHelper的maven依赖及插件配置 < dependency > < groupId > com.github.pagehelper </ groupId > < artifactId > pagehelper </ artifactId > < version > 4.1.6 </ version > </ dependency > PageHelper除了本身的jar包外，它还依赖了一个叫jsqlparser的jar包，使用时

How to add new condition with JSqlParser?

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问题 I want to add new condition to my sql. For example If query is; SELECT EMP_ID, FIRST_NAME FROM EMPLOYEES; I can add new where cause with this codes; @Override protected void setLimit(final PlainSelect ps,final long rowLimit) { Expression where = ps.getWhere(); if(where == null) { try { where = CCJSqlParserUtil.parseCondExpression("ROWNUM < " + (rowLimit+1) ); } catch (JSQLParserException e) { e.printStackTrace(); } } ps.setWhere(where); } This codes changes the query to SELECT EMP_ID, FIRST

MySQL建表语句转PostgreSQL建表语句全纪录

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个人习惯用MySQL workbench EER数据建模，然后生成SQL语句到数据库中执行，这样表之间的关系比较直观。像下面这样：画图正向工程，生成DDL语句：忽略生成外键，以及外键索引啥的：生成的DDL语句：到数据库执行。踩坑了最近团队微调，我被调整到另一个小团队。前两天接了个新需求，于是我依然使用MySQL workbench EER建模，结果好不容易建模完成了，却被告知这个项目用的数据库是PostgreSQL！于是就面临如下几种选择：重新找个支持导出PostgreSQL DDL语句的建模软件，再弄一遍。据我所知，macOS平台里没啥好的数据建模软件… PowerDesigner用不了（除非装虚拟机，或者Wine）； Navicat太难用了（居然有人说Navicat是最好的数据库客户端，我只能给一个大写的服，在我看来，这货连IDEA自带数据库管理都比不上……这观点可能有点偏激，但现状是我做个查询，Navicat把查询按钮藏得很深）； IDEA宣布会开发类似功能，但一直没有动静；开源的PDMan，体验挺不错，但也得连个数据库控制版本。依然用MySQL workbench导出DDL，然后自己将MySQL DDL转换成PostgreSQL DDL。我选择了自己转换SQL语句。开源的DDL转换工具既然要转换SQL语句，我心想，业界肯定有相关的工具啊

MyBatis-PageHelper分页工具类

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PageHelper 是 MyBatis 中非常方便的第三方分页插件官方文档： https://github.com/pagehelper/Mybatis-PageHelper/blob/master/README_zh.md 我们可以对照官方文档的说明，快速的使用插件 PageHelper 的使用步骤导入相关包 pagehelper-x.x.x.jar 和 jsqlparser-0.9.5.jar 在 MyBatis 全局配置文件中配置分页插件 <plugins> <plugin interceptor="com.github.pagehelper.PageInterceptor"></plugin> </plugins> PageHelper分页工具类 /** * 首页上一页 1 2 3 4 5 下一页末页 * */ public class PageUtil { public static String getPageInfo(PageInfo<Emp> pageInfo, HttpServletRequest request) { String path = request.getContextPath() + "/"; StringBuilder builder = new StringBuilder(); //拼接首页 builder.append("<a

【SSM_09】Mybatis-多表操作、插件

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一、映射文件增强 1. 动态 sql ① if 标签 <select id="find" parameterType="demo" resultType="demo"> select * from test  <where>  <if test="id != null"> and id = #{id} </if> <if test="name != null"> and name = #{name} </if> <if test="phone != null"> and phone = #{phone} </if> </where> </select> ---------------------------------------------------------------------------------------------------------------- ② forearch 标签 <select id="in" parameterType="demo" resultType="demo"> select * from test <where> <!-- 传入一个容器

Parsing table and column names from SQL/HQL Java

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问题 I am looking for an open source API in Java to parse an SQL / HQL query so that it gives me the column names and the table names used in it. I tried using JSQLParser which gives me the table names used in the query. But I don't see a support for getting the column names used in the query. Is there any other API which can help me with this? I am aware of General SQL parser but it seems to be a paid one. Here is the code snippet using JSQLParser which gives me the table names in the query:

JSqlParser - Pretty print where clause

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问题 I have started to use JSqlParser, i can parse a Where clause but i don't manage to go further with it. JSqlParser github link Indeed, i have tried to Override visit methods but don't understand how to reach my goal. Let's say i have: (a=1 AND (b=2 OR (c=3 AND d=4))) OR e=2 as input and i would like as output: -> a=1 -> AND --> b=2 --> OR ---> c=3 ---> AND ---> d=4 -> OR -> e=5 My final goal is not a pretty print, but to understand how to know the current depth of the print at a given state.

How to do unit testing of Visitors in Jsqlparser?

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问题 I have implemented the Visitors of JSqlparser to parse SQL queries. The code is working absolutely fine. I am not sure how to do unit testing for those visitors. For example I have the following sql statement: Select a.a1, a.a2 from foo as a To parse it I have implemented StatementVisitor interface and my code goes like this: public class StmntVisitorImpl implements StatementVisitor { @Override public void visit(Select select) { LOG.debug("Begin Select visit : "+select.toString());

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