ALTERTABLEtestDROPc3; 设置表格 test 的副本数,并且增加列 c5 ALTERTABLEtestSETREPLICA_NUM=2,ADDCOLUMNc5INT; 清除分区表 t_log_part_by_range 的分区 M202001 和 M202002 中的全部数据。 obclient>CREATETABLEt_log_part_by_range(log_idbigintNOTNULL,log_valuevarchar(50),log_datetimestampNOTNULL)PART...
ALTER TABLE 表名称 DROP CONSTRAINT fk_约束名 CHECK(检查)更新: 新增检查约束: ALTER TABLE 表名称 ADD CHECK (列名称 比较符 "条件") 新增多列检查约束: ALTER TABLE 表名称 ADD CONSTRAINT chk_约束名 CHECK (列名称 比较符 "条件" AND 列名称 比较符 "条件" ...) 撤销检查约束: ALTER TABLE 表名称...
删除分区数据时,请尽量避免该分区上存在活动的事务或查询,否则可能会导致 SQL 语句报错,或者一些异常情况。 RENAME [TO] table_name表重命名。 RENAME {INDEX | KEY}重命名索引或键。 DROP [TABLEGROUP]删除表组。 DROP [FOREIGN KEY]删除外键。 [SET] table_option设置表级属性,可选以下参数: ...
•Altertable...add[column_name]•Altertable...addconstraint[name]unique[index/key][name]•Altertable...addconstraint[name]foreignkey(column_name)referencestable_name(column_name) •Altertable...dropcolumn[column_name]•Altertable...drop[index/key][index_name] 3>.案例展示 mysql> ALTER ...
ALTER TABLE table-name 1ADDCOLUMNcolumn-definitionALTERCOLUMNcolumn-alterationRENAME COLUMNsource-column-nameTOtarget-column-nameDROPCOLUMNcolumn-nameRESTRICTADD PERIODFORperiod-definitionADDunique-constraintreferential-constraintcheck-constraint4DROPRPRIMARY KEYUNIQUEFOREIGN KEYCHECKCONSTRAINTconstraint-nameADD PARTITIO...
alter table 表名 add unique emp_name2(cardnumber);//empname 类型 为String 字符串类型 10)创建联合唯一索引 alter table 表名 ADD UNIQUE INDEX 索引名 (列名1,列名2); alter ignore table 表名 add unique index(user_id,user_name);//它会删除重复的记录(别怕,会保留一条),然后建立唯一索引,高效而...
ALTER TABLE nested_skill_table ADD UNIQUE (a); The following statement alters the storage table for a nested table of REF values to specify that the REF is scoped: CREATE TYPE emp_t AS OBJECT (eno number, ename char(31)); CREATE TYPE emps_t AS TABLE OF REF emp_t; CREATE TABLE emp...
For more information, see Section 13.1.18, “CREATE TABLE Statement”. The word COLUMN is optional and can be omitted. Multiple ADD, ALTER, DROP, and CHANGE clauses are permitted in a single ALTER TABLE statement, separated by commas. This is a MySQL extension to standard SQL, which ...
ALTER TABLE modifies a table definition by altering, adding, or dropping columns and constraints. ALTER TABLE also reassigns and rebuilds partitions, or disables and enables constraints and triggers.
Jira Link: DB-1178 This is a master issue that keeps track of ALTER TABLE variants. The checkmark means that the statement is already supported. Add / remove / rename columns, constraints Status Feature Comments ✅ ALTER TABLE name ADD [C...