This statement inserts a new record into a table with specified values.ġ8. INSERT INTO table_name (column1, column2, column3. This statement deletes specified columns from the existing table.ġ7. This statement adds columns to the existing table. ALTER TABLE table_name ADD(column1, column2, column3.) This statement renames the table to a new name.ġ5. Old_table_name : name of the previous table. RENAME TABLE old_table_name TO new_table_name This statement deletes the mentioned table.ġ4. It is used to generate a unique identification field for new row. Storage engine selected is ‘InnoDB’ allowing foreign key constraint and related transactions. Note : You have ‘id’ column as AUTO_INCREMENT with a primary key constraint which ensures that each id is incremented value, avoiding duplication. 'profile' VARCHAR(40) DEFAULT 'engineer', This statement creates a new table with the given columns. When the developer start building an application, he needs to create database tables. CREATE TABLE table_name(column1, column2, column3.) Note : User has to be very careful before deleting a database as it will lose all the crucial information stored in the database.ġ1. Multi-line comments or single-line or end-of-line comment. SELECT can also be used for more than one or many columns.Ĭomments are of two types. SELECT can be used for executing an expression or evaluating an in-built function. This executes SELECT statement without any table. This query shows the current date and time. MySQL queries mostly starts with SELECT statement. This shows the complete CREATE TABLE statement used by MySQL for creating the table. This shows all the tables in the selected database as a information. This describes the columns of the table_name with respect to Field, Type, Null, Key, Default, Extra. To display the current database name which is set, use syntax SELECT DATABASE() This sets the database as the current database in the MySQL server. A ‘test’ database is meant for testing purpose which is provided during installation. Note : The databases ‘information_schema’, ‘mysql’ and ‘performance_schema’ are system databases which are used internally by MySQL server. This displays information of all the existing databases in the server. Some of the commonly used MySQL queries, operators, and functions are as follows : Queries can be understood as the commands which interacts with database tables to work around with data.
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