1. Define basic tables 1. Commonly used integrity constraints Primary code constraints primary key foreign key constraints foreign key uniqueness constraint unique non-nullity constraint not null value constraints check 2. Example questions [Example 1] Create a “student” table Student, which consists of five attributes: student number Sno, name Sname, gender Ssex, age Sage, and department […]
Tag: grammar
SQL Grammar Practice (2): Basic Grammar
Practice code Practice based on a very detailed introduction to SQL syntax written by a great guy. It is highly recommended. The link is as follows: Jump to the original text –This table is supplemented based on the following content. It is no problem for practice use. CREATE TABLE friend( fid INT NOT NULL, NAME […]
Compilation Principle: Special Topic 4 Operator-First Grammar Analysis Design Principle and Implementation
Article directory 1. Experimental purpose 2. Experimental requirements 3. Program implementation 3.1. Introduction to relevant environments 3.2. Main data structures 3.3. Program structure description 3.3.1. Design method 3.3.2. Function definition 4. Program testing 5. Experiment summary 5.1. Technical difficulties and solutions 5.2. Experimental thoughts and experience summary 1. Experiment purpose Through experiments, master and implement […]
Compilation Principles: Special Topic 3_LL(1) Grammar Analysis Design Principles and Implementation
Article directory 1. Experimental purpose 2. Experimental requirements 3. Program implementation 3.1. Introduction to relevant environments 3.2. Main data structures 3.3. Program structure description 3.3.1. Design method 3.3.2. Function definition 4. Program testing 5. Experiment summary 5.1. Technical difficulties and solutions 5.2. Experimental thoughts and experience summary 1. Experiment purpose Through experiments, master LL(1) grammar […]
### Cause: dm.jdbc.driver.DMException: Error near line 59, column 54 [=]: syntax parsing error; bad SQL grammar []; nested
Error reporting ### Cause: dm.jdbc.driver.DMException: An error occurred near line 59, column 54 [=]: Syntax parsing error ; bad SQL grammar []; nested exception is dm.jdbc.driver.DMException: An error occurred near line 59, column 54 [=]: Syntax parsing error at org.springframework.jdbc.support.SQLStateSQLExceptionTranslator.doTranslate(SQLStateSQLExceptionTranslator.java:99) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:82) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:82) at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:73) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:446) at com.sun.proxy.$Proxy134.selectList(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:230) […]
Grammar rules and usage of Less language
Grammar rules and usage of Less language 1. Less introduction Less (Leaner Style Sheets) is a backward-compatible CSS extension language that belongs to the category of CSS preprocessor. It extends the CSS language and adds features such as variables, mixins, and functions, making CSS easier to maintain and expand. Less official website: lesscss Less Chinese […]
Regular grammar context-free grammar, regular grammar is several types of grammar
Hello everyone, the editor is here to answer the following questions for you, regular grammar, context-free grammar, what types of grammar are regular grammars, let us take a look today! Easily understand python regular expressions (super detailed, with examples) When you need to match strings through regular expressions in Python, you can use a module […]
ES6-grammar parsing-let-const, etc.
theme: channing-cyan Learn with coderwhy 1. Literal enhancement Object literals are enhanced in ES6, called Enhanced object literals. The enhancement of literals mainly includes the following parts: Property abbreviation: Property Shorthand Method abbreviation: Method Shorthand Computed property names: Computed Property Names “`js var name = ‘mint’ var age = 18 var obj = { // […]
Lua script from beginner to proficient [Summary] Learn Lua script and grammar examples in one article
Article directory 0.Preface background application 1. Study Outline 1. Learn basic grammar: 2. Understand functions and modules: 3. Go deep into the data structure: 4. Advanced features and techniques: 5. Practical projects: 2. Lua script 2.1 Learn basic grammar 2.2 Understand functions and modules 2.3 In-depth data structure 2.4 Advanced features and techniques 3. Advanced […]
C++ Elementary Grammar – new, delete create/destroy dynamic memory space
Preface: In C language, there are malloc, realloc, calloc to open up dynamic memory space, and free to destroy dynamic memory space. In C++, use new to open up dynamic memory space, and delete to destroy dynamic memory space. It not only simplifies the operation, but more importantly, solves the initialization problem of custom types. […]