Mysql insert into field plus text11/2/2023 ![]() Hence, it is best to treat identifiers as case-sensitive. The names or identifiers (database names, table names, column names, etc.) are case-sensitive in some systems, but not in other systems. For clarity, they are shown in uppercase. The SQL keywords and commands are NOT case-sensitive. A table is made up of columns (or fields) and rows ( records). Each database consists of one or more tables. SHOW WARNINGS - Show the warnings of the previous statement An Example for the Beginners (But NOT for the dummies)Ī MySQL database server contains many databases (or schemas). , columnNValue) - Insert on selected Columns VALUES ( column1Value, column2Value.) - Insert on all Columns SHOW CREATE TABLE tableName - Show the CREATE TABLE statement for this tableName - Row-Level Modify a table, e.g., ADD COLUMN and DROP COLUMNĪLTER TABLE tableName ADD columnDefinitionĪLTER TABLE tableName ADD FOREIGN KEY ( columnNmae) REFERENCES tableName ( columnNmae) ALTER TABLE tableName DROP FOREIGN KEY constraintName ![]() SHOW TABLES - Show all the tables in the default databaseĭESCRIBE|DESC tableName - Describe the details for a tableĪLTER TABLE tableName. įOREIGN KEY ( columnNmae) REFERENCES tableName ( columnNmae) SHOW CREATE DATABASE databaseName - Show the CREATE DATABASE statement - Table-LevelĬolumnName columnType columnAttribute. SELECT DATABASE() - Show the default database USE databaseName - Set the default (current) database SHOW DATABASES - Show all the databases in this server ![]() Database-LevelĭROP DATABASE databaseName - Delete the database (irrecoverable!)ĭROP DATABASE IF EXISTS databaseName - Delete if it existsĬREATE DATABASE databaseName - Create a new databaseĬREATE DATABASE IF NOT EXISTS databaseName - Create only if it does not exists Summary of MySQL Commands Used in this Tutorialįor detailed syntax, check MySQL manual "SQL Statement Syntax". Use the TEXT data type to store long texts in the database.Read " How to Install MySQL and Get Started" on how to install, customize, and get started with MySQL.The LONGTEXT can store text data up to 4GB, which is quite big in common scenarios. ) Code language: SQL (Structured Query Language) ( sql ) LONGTEXT – 4GB (4,294,967,295 characters) ![]() The MEDIUMTEXT is useful for storing quite large text data like the text of a book, white papers, etc. The MEDIUMTEXT can hold up to 16MB text data which is equivalent to 16,777,215 characters. The following example adds the column body with the TEXT type to the articles table using the ALTER TABLE statement: ALTER TABLE articlesĪDD COLUMN body TEXT NOT NULL AFTER summary Code language: SQL (Structured Query Language) ( sql ) MEDIUMTEXT – 16MB (16,777,215 characters) The TEXT datatype also requires 2 bytes overhead. The TEXT data type can hold up to 64 KB which is equivalent to 65535 (2^16 – 1) characters. ) Code language: SQL (Structured Query Language) ( sql ) TEXT – 64KB (65,535 characters) The following example creates a new table called articles that has a summary column with the data type is TINYTEXT: CREATE TABLE articles ( For example, you can use the TINYTEXT to store the excerpt of a blog post. In practice, you use TINYTEXT for the column that requires less than 255 characters, has inconsistent length, and does not require sorting. The maximum number of characters that TINYTEXT can store is 255 ( 2^8 = 256, 1 byte overhead). The following shows the size of each TEXT type with the assumption that you are using a character set that takes one byte to store a character TINYTEXT – 255 Bytes (255 characters) Therefore, when you query TEXT data, MySQL has to read from it from the disk, which is much slower in comparison with CHAR and VARCHAR. Note that the TEXT data is not stored in the database server’s memory. Unlike CHAR and VARCHAR type, you don’t have to specify a storage length when you use a TEXT type for a column.Īlso, MySQL does not remove or pad spaces when retrieving or inserting text data like CHAR and VARCHAR. In practice, you often use the TEXT data type for storing articles in news sites, and product descriptions in e-commerce sites. The TEXT is useful for storing long-form text strings that can take from 1 byte to 4GB. Besides CHAR and VARCHAR character types, MySQL supports the TEXT type that provides more features.
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