General MySQL Oracle SQL Server

<< < … 5 6 7 8 9 10 11 12 13 14 15 … > >>   ∑:380  Sort:Date

Violation of Unique Value Constraint in MySQL
What Happens If Unique Value Constraints Are Violated in MySQL? If you are inserting a new record that has values violating a unique constraint, you will get an error. Note that primary key column has a unique value constraint by default. The following tutorial exercise gives you some good examples:... 2018-01-16, 2488🔥, 0💬

Inner Join with the WHERE Clause in MySQL
How To Write an Inner Join with the WHERE Clause in MySQL? If you don't want to use the INNER JOIN ... ON clause to write an inner join, you can put the join condition in the WHERE clause as shown in the following query example: mysql&gt; SELECT l.id, l.url, r.comment FROM fyi_links l, fyi_rates... 2017-09-28, 2487🔥, 0💬

Drop an Existing View in MySQL
How To Drop an Existing View in MySQL? If you have an existing view, and you don't want it anymore, you can delete it by using the "DROP VIEW viewName" statement as shown in the following script: mysql&gt; DROP VIEW faqComment; Query OK, 0 rows affected (0.00 sec) mysql&gt; SELECT * FROM faq... 2018-01-24, 2486🔥, 0💬

Experiment with Dead Locks in MySQL
How To Experiment Dead Locks in MySQL? If you want to have some experience with dead locks, you can create two windows running two mysql transactions in two sessions at the REPEATABLE READ transaction isolation level. Then run some UPDATE statements as shown in the tutorial exercise below: (session ... 2017-07-21, 2485🔥, 0💬

Count Number of Rows with SELECT Statements in MySQL
How To Use SELECT Statement to Count Number of Rows in MySQL? If you want to count the number of rows, you can use the COUNT(*) function in the SELECT clause. The following tutorial exercise shows you some good example: mysql&gt; SELECT COUNT(*) FROM fyi_links; +----------+ | COUNT(*) | +-------... 2018-01-06, 2484🔥, 0💬

Viewing Log File with "mysqlbinlog" in MySQL
How To Use mysqlbinlog to View Binary Logs in MySQL? If you have binary logs turned on, you can use "mysqlbinlog" to view the binary log files. The tutorial exercise below shows you how to view two binary files together: &gt;cd \mysql\bin &gt;mysql -u root -pretneciyf test &gt;mysqlbinlo... 2017-11-29, 2484🔥, 0💬

Retrieving the Last Sequence ID in MySQL
How To Get the Last ID Assigned by MySQL in MySQL? If you use an ID column with AUTO_INCREMENT attribute, you can use the mysql_insert_id() function to get the last ID value assigned by the MySQL server, as shown in the sample script below: &lt;?php include "mysql_connection.php"; $sql = "INSERT... 2017-09-12, 2484🔥, 0💬

Entering Character Strings in MySQL
How To Include Character Strings in SQL statements in MySQL? If you want to include character strings in your SQL statements, you need to quote them in one of the following formats: Using single quotes. For example 'FYIcenter.com'. Using double quotes. For example "FYI Center". Using single quotes p... 2018-04-12, 2482🔥, 0💬

Creating a Test Table in MySQL
How To Create a Testing Table in MySQL? If you want to practice DML statements, like INSERT, UPDATE and DELETE, you should create a testing table. The tutorial exercise shows you a good example: mysql&gt; CREATE TABLE fyi_links (id INTEGER PRIMARY KEY, url VARCHAR(80) NOT NULL, notes VARCHAR(102... 2018-01-24, 2478🔥, 0💬

Ways to Start MySQL Server in MySQL
How To Start MySQL Server Daemon mysqld in MySQL? There are a number of ways to start MySQL server daemon, mysqld: Double click on the file name, mysqld.exe, in a file explorer window. This is an easy way to start the server. But you will not be able to specify any command line options. Enter "mysql... 2017-12-04, 2472🔥, 0💬

Define the ID Column as Auto-Incremented in MySQL
How To Define the ID Column as Auto-Incremented in MySQL? Many tables require an ID column to assign a unique ID number for each row in the table. For example, if you have a table to hold forum member profiles, you need an ID number to identify each member. To allow MySQL server to automatically ass... 2017-09-12, 2472🔥, 0💬

Transaction Committed when DDL Statement Executed in MySQL
What Happens to the Current Transaction If a DDL Statement Is Executed in MySQL? If a DDL statement is executed, the current transaction will be committed and ended. All the database changes made in the current transaction will become permanent. This is called an implicit commit by a DDL statement. ... 2016-10-17, 2470🔥, 0💬

Query with a Full Outer Join in MySQL
How To Write a Query with a Full Outer Join in MySQL? There is no way to do full outer join in MySQL. It does not support this feature at the current MySQL release.   ⇒ Inner Join with the WHERE Clause in MySQL ⇐ Query with a Right Outer Join in MySQL ⇑ SELECT Statements with JOIN and Subqueries in... 2017-09-28, 2469🔥, 0💬

Deleting Existing Rows in MySQL
How To Delete Existing Rows in a Table in MySQL? If you want to remove a row from a table, you can use the DELETE statement with a WHERE clause to identify the row. The following sample script deletes one row: &lt;?php include "mysql_connection.php"; $sql = "DELETE FROM fyi_links WHERE id = 1102... 2017-06-28, 2469🔥, 0💬

Execute SQL Statements in MySQL
How To Execute a SQL Statement in MySQL? You can run any types of SQL statements through the mysql_query() function. It takes the SQL statement as a string and returns different types of data depending on the SQL statement type and execution status: Returning FALSE, if the execution failed. Returnin... 2017-10-23, 2468🔥, 0💬

Using Regular Expression with REGEXP in MySQL
How To Use Regular Expression in Pattern Match Conditions in MySQL? If you have a pattern that is too complex for LIKE to handle, you can use the regular expression pattern condition: REGEXP. The following tutorial exercise provides you some good examples: SELECT 'FYICenter.com' REGEXP '.*fyi.*' FRO... 2018-03-24, 2465🔥, 0💬

What Is SQL Standard in MySQL
What Is SQL Standard in MySQL? SQL, SEQUEL (Structured English Query Language), is a language for RDBMS (Relational Database Management Systems). SQL was developed by IBM Corporation. SQL became an ANSI standard, called SQL-87, in 1986. ISO made a major revision, called SQL-92, in 1992. The latest r... 2018-04-21, 2464🔥, 0💬

IS_IPV4() - Detecting IPv4 Address
How to detect an IPv4 Address using the IS_IPV4() function? IS_IPV4(ip) is a MySQL built-in function that returns 1 if the given value is a valid IPv4 address, 0 otherwise. For example: SELECT IS_IPV4('10.0.5.9'), IS_IPV4('10.0.5.256'); -- +---------------------+------- ----------------+-- | IS_IPV4... 2026-02-02, 2462🔥, 0💬

ROLES_GRAPHML() - User Role Graph in GraphML Format
How to obtain User Role Graph in GraphML Format using the ROLES_GRAPHML() function? ROLES_GRAPHML() is a MySQL built-in function that returns user role graph in GraphML format. For example: SELECT ROLES_GRAPHML(); -- +----------------------------- ------------------------------ ---------+-- | ROLES_G... 2025-02-16, 2460🔥, 0💬

What Is Commit in MySQL
What Is Commit in MySQL? Commit is a way to terminate a transaction with all database changes to be saved permanently to the database server.   ⇒ What Is RollBack in MySQL ⇐ What Is Transaction in MySQL ⇑ Database Basics and Terminologies in MySQL ⇑⇑ MySQL Database Tutorials 2016-10-16, 2460🔥, 0💬

SYSTEM_USER() - Synonym for USER()
What's the difference between SYSTEM_USER() and USER() functions? SYSTEM_USER() is a synonym for the USER() function. Related MySQL functions: USER() - Login Name of Current User SESSION_USER() - Synonym for USER() SYSTEM_USER() - Synonym for USER() CURRENT_USER() - Authentication Name of Current Us... 2025-01-07, 2457🔥, 0💬

What Is Binary Log File in MySQL
What Is Binary Log File in MySQL? MySQL server binary log file plays an important role in restoring database changes to the server. Main features on binary log files are: Binary logs can be turned on by "--log-bin=fileBaseName" option on "mysqld". Binary logs only records statements that are changin... 2017-11-29, 2453🔥, 0💬

Using SELECT Statements in Views in MySQL
Can SELECT Statements Be Used on Views in MySQL? Select (query) statements can be used on views in the same way as tables. The following tutorial exercise helps you creating a view and running a query statement on the view: mysql&gt; CREATE VIEW myLinks AS SELECT * FROM fyi_links WHERE url LIKE ... 2018-01-06, 2442🔥, 0💬

Drop an Existing Index in MySQL
How To Drop an Existing Index in MySQL? If you don't need an existing index any more, you should delete it with the "DROP INDEX indexName ON tableName" statement. Here is an example SQL script: mysql&gt; DROP INDEX tip_subject ON tip; Query OK, 0 rows affected (0.13 sec) Records: 0 Duplicates: 0... 2018-02-14, 2439🔥, 0💬

<< < … 5 6 7 8 9 10 11 12 13 14 15 … > >>   ∑:380  Sort:Date

General MySQL Oracle SQL Server