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22 Φεβ 2017 · Using Exists statement to delete data from table: IF EXISTS(SELECT 1 FROM Your_table WHERE user_id = user_id) BEGIN DELETE FROM Your_table WHERE user_id= user_id END Delete table from database : IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'TheSchema' AND TABLE_NAME = 'TheTable') BEGIN --Your delete statement END
The SQL cheat sheet provides you with the most commonly used SQL statements for your reference. You can download the SQL cheat sheet as follows: Download 3-page SQL cheat sheet in PDF format.
To remove an existing database from a SQL Server instance, you use the DROP DATABASE statement. The DROP DATABASE statement allows you to delete one or more databases with the following syntax: DROP DATABASE [ IF EXISTS ] database_name [,database_name2,...];
The SQL DELETE statement is a fundamental SQL command that deletes existing records in a database. These notes explain the syntax needed to write effective DELETE SQL queries. You’ll learn about the DELETE FROM WHERE conditions command, which allows you to specify the exact SQL rows to delete.
A row can be deleted with the DELETE statement. Syntax for DELETE: DELETEFROM table_name WHERE condition; DELETEFROM Student WHERE StudentID = ‘103’; Remove all rows (records) from a table without deleting the table with DELETE: DELETEFROM table_name; 5. Retrieving Data. We can display one or more columns when we retrieve data from a table.
Download this eBook for free Chapters. Chapter 1: Getting started with SQL; Chapter 2: ALTER TABLE; Chapter 3: AND & OR Operators; Chapter 4: Cascading Delete; Chapter 5: CASE; Chapter 6: Clean Code in SQL; Chapter 7: Comments; Chapter 8: Common Table Expressions; Chapter 9: CREATE Database; Chapter 10: CREATE FUNCTION; Chapter 11: CREATE TABLE
The SQL DROP DATABASE Statement. The DROP DATABASE statement is used to drop an existing SQL database. Syntax. DROP DATABASE databasename; Note: Be careful before dropping a database. Deleting a database will result in loss of complete information stored in the database! DROP DATABASE Example.
