Tag：sql
-
Mysql Query Statements
simple query ## Direct query Syntax: select field from table name; For example, select name, age from student; Ans: Query name and age from the student table. ## Conditional queries Syntax: select field from table name where Condition; For example, select name from student where age = 15; Ans: Query the student table for name […]
-
JDBC Connecting to MySQL
catalogs I. Beginning II. Introduction 1, the concept of JDBC 2、Functions of JDBC 3, JDBC common interfaces and classes III. Database creation (MySQL) 1. Connecting to MySQL (1), register the driver (2) Getting Connected (3), get the executor connection (4), execute the SQL statement, and accept the results (5), processing results (6) Release of resources […]
-
MySQL Table Additions, Deletions and Changes (Basic)
Article Catalog ☕️1. CRUD☕️ 2. Create 2.1 Single-line data + full-column insertion 2.2 Multiple Rows + Specified Column Insertion 2.3 Insertion format on time (homework data table): 3. Query (Retrieve) 3.1 Full-column queries 3.2 Specified Column Queries 3.3 Query Fields as Expressions 3.4 Alias 3.5 De-weighting: DISTINCT 3.6 Sorting: ORDER BY 3.7 Conditional queries: WHERE […]
-
DML statements in SQL
preamble Previously we have explained DDL statements in SQL statements. Today we will continue with the DML statement of SQL. DML is the Data Manipulation Language.Used to add, delete, and change data operations on the tables in the library.。 1. Add data to the specified field(INSERT) 2. Modify data(UPDATE) 3. Delete data(DELETE) catalogs preamble I. […]
-
Resolved the Java. SQL. SQLNonTransientConnectionException: Could not create connection to the database server abnormal correctly solved
Resolved Java. SQL. SQLNonTransientConnectionException: Could not create connection to the database server abnormal correct solution, kiss measuring effective!!!!!! Article Catalog report an error problemSolutionscureexchanges report an error problem java.sql.SQLNonTransientConnectionException:Could not create connection to database server Solutions The error “java.sql.SQLNonTransientConnectionException:Could not create connection to database server” is usually caused by an inability to connect to the […]