Database
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What is the difference between syntax for adding columns in different database systems
What is the difference between syntax for adding columns in different database systems
不同数据库系统添加列的语法为：MySQL：ALTER TABLE table_name ADD column_name data_type;PostgreSQL：ALTER TABLE table_name ADD COLUMN column_name data_type;Oracle：ALTER TABLE table_name ADD (column_name data_type);SQL Server：ALTER TABLE table_name ADD column_name data_
不同数据库系统添加列的语法
MySQL
ALTER TABLE table_name ADD column_name data_type;
PostgreSQL
ALTER TABLE table_name ADD COLUMN column_name data_type;
Oracle
ALTER TABLE table_name ADD (column_name data_type);
SQL Server
ALTER TABLE table_name ADD column_name data_type;
SQLite
ALTER TABLE table_name ADD COLUMN column_name data_type;
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