需求分析:前端传过来的字段,后端组装成sql的建表语句。
例子:
前端传过来:表名,字段名称,字段类型,字段长度,非空,是否主键等字段。
具体例子:username(主键) varchar(30),pwd varchar(30),user表名,用户表:中文名。后端需要组装成建表语句。
CREATE TABLE USER (
username VARCHAR ( 30 ) NOT NULL COMMENT '用户名',
pwd VARCHAR ( 30 ) NOT NULL COMMENT '密码',
PRIMARY KEY ( username ) ) ENGINE = INNODB DEFAULT CHARSET = utf8 COMMENT = '用户表'
实现
public String transfer(String objectTableName, String objectCNName, List<DataObjectAttr> dataObjectAttrList) {
StringBuilder start = new StringBuilder().append("CREATE TABLE ")
.append(objectTableName).append("(");
StringBuilder builder = new StringBuilder();
for (DataObjectAttr dataObjectAttr : dataObjectAttrList) {
String field_name = dataObjectAttr.getFIELD_NAME();
String field_type = dataObjectAttr.getFIELD_TYPE();
String field_length = dataObjectAttr.getFIELD_LENGTH();
String field_notes = dataObjectAttr.getFIELD_NOTES();
String is_primary_key = dataObjectAttr.getIS_PRIMARY_KEY();//0:不是主键,1:主键
String field_is_null = dataObjectAttr.getFIELD_IS_NULL();//0 空,1:非空
builder.append(field_name).append(" ");
builder.append(field_type).append("(").append(field_length).append(")").append(" ");
if (field_is_null.equals(0)) {
builder.append(" DEFAULT NULL ");
} else {
builder.append(" NOT NULL ");
}
builder.append("COMMENT").append(" ").append("'").append(field_notes).append("'").append(",");
if (is_primary_key.equals("1")) {
builder.append("PRIMARY KEY").append("(").append(field_name).append(")");
}
}
StringBuilder end = new StringBuilder().append(")").append("ENGINE=InnoDB DEFAULT CHARSET=utf8").append(" ")
.append("COMMENT=").append("'").append(objectCNName).append("'");
StringBuilder sqlString = start.append(builder).append(end);
return sqlString.toString();
}
