以下的文章主要讲述的是MySQL表修改，即，增加或是删减列与创建或取消索引等相关操作，我们大家都知道MySQL在创建一个相关的数据库后，如果接着继续创建一张表而且加如了一些字段，那么我以后还想再增加字段怎么做？
解答：使用alter table(修改表)!
ALTER TABLE语法：
ALTER [IGNORE] TABLE tbl_name alter_specification [, alter_specification] ... alter_specification: ADD [COLUMN] column_definition [FIRST | AFTER col_name ] | ADD [COLUMN] (column_definition,...) | ADD INDEX [index_name] [index_type] (index_col_name,...) | ADD [CONSTRAINT [symbol]] PRIMARY KEY [index_type] (index_col_name,...) | ADD [CONSTRAINT [symbol]] UNIQUE [index_name] [index_type] (index_col_name,...) | ADD [FULLTEXT|SPATIAL] [index_name] (index_col_name,...) | ADD [CONSTRAINT [symbol]] FOREIGN KEY [index_name] (index_col_name,...) [reference_definition] | ALTER [COLUMN] col_name {SET DEFAULT literal | DROP DEFAULT} | CHANGE [COLUMN] old_col_name column_definition [FIRST|AFTER col_name] | MODIFY [COLUMN] column_definition [FIRST | AFTER col_name] | DROP [COLUMN] col_name | DROP PRIMARY KEY | DROP INDEX index_name | DROP FOREIGN KEY fk_symbol | DISABLE KEYS | ENABLE KEYS | RENAME [TO] new_tbl_name | ORDER BY col_name | CONVERT TO CHARACTER SET charset_name [COLLATE collation_name] | [DEFAULT] CHARACTER SET charset_name [COLLATE collation_name] | DISCARD TABLESPACE | IMPORT TABLESPACE | table_options | partition_options | ADD PARTITION partition_definition | DROP PARTITION partition_names | COALESCE PARTITION number | REORGANIZE PARTITION partition_names INTO (partition_definitions) | ANALYZE PARTITION partition_names | CHECK PARTITION partition_names | OPTIMIZE PARTITION partition_names | REBUILD PARTITION partition_names | REPAIR PARTITION pa
上面说了这么多内容，是关于对MySQL表修改的介绍，不知道各位对MySQL的认识是不是更上一层楼了，时时关注ITJS，学习最新Mysql技术。