解决方案 在MySQL数据连接高级属性中,连接属性新增如下参数之一即可,这样就可以在目的端正常建表。 “tinyInt1isBit”参数,参数值设为“false”。 “mysql.bool.type.transform”参数,参数值设为“false”。 图1 添加连接属性 父主题: 故障处理类 意见反馈 文档内容是否对您有帮助? 提供反馈 我们...
AccessPath *path, JOIN *join, bool eligible_for_batch_mode) {...switch (path->type) {case AccessPath::TABLE_SCAN: {const auto ¶m = path->table_scan(); iterator = NewIterator<TableScanIterator>( thd, param.table
transform_scalar_subqueries_to_join_with_derived:Transform eligible scalar subqueries to derived tables. flatten_subqueries:Convertsemi-joinsubquery predicates into semi-join join nests. Convert candidate subquery predicates into semi-join join nests. This transformation is performed once in query lifetime ...
遍历这些子查询,判断是否可以增加一个额外的转换(transform_grouped_to_derived):把隐性的GROUP BY标量子查询变成Derived Table。 SELECT SUM(c1), (SELECT SUM(c1) FROM t3) scalar FROM t1; 转换为=> SELECT derived0.summ, derived1.scalar FROM (SELECT SUM(a) AS summ FROM t1) AS derived0 LEFT JOIN...
首先从JOIN条件、WHERE条件、HAVING条件和SELECT list中收集可以转换的标量子查询（Item::collect_scalar_subqueries）。遍历这些子查询，判断是否可以增加一个额外的转换（transform_grouped_to_derived）：把隐性的GROUP BY标量子查询变成Derived Table。SELECT SUM(c1), (SELECT SUM(c1) FROM t3) scalar FROM t1;...
tinyInt1isBit=false或mysql.bool.type.transform=false:MySQL默认开启配置tinyInt1isBit=true,将TINYINT(1)当作BIT也就是Types.BOOLEAN来处理,会将1或0读取为true或false从而导致迁移失败,此时可关闭配置避免迁移报错。 useCursorFetch=false:CDM作业默认打开了JDBC连接器与关系型数据库通信使用二进制协议开关,即useCur...
Transform eligible scalar subqueries to derived tables. flatten_subqueries : Convert semi-join subquery predicates into semi-join join nests. Convert candidate subquery predicates into semi-join join nests. This transformation is performed once in query lifetime and is irreversible. ...
$$= NEW_PTN PTI_truth_transform(@$, $2, Item::BOOL_NEGATED); } | row_subquery { $$= NEW_PTN PTI_singlerow_subselect(@$, $1); } | '(' expr ')' { $$= $2; if ($$ != nullptr) $$->m_pos = @$; } | '(' expr ',' expr_list ')' ...
unique_ptr_destroy_only<RowIterator> CreateIteratorFromAccessPath( THD *thd, AccessPath *path, JOIN *join, bool eligible_for_batch_mode) { ... switch (path->type) { case AccessPath::TABLE_SCAN: { const auto ¶m = path->table_scan(); iterator = NewIterator<TableScanIterator>( thd...
{ return true; } mysql_query的返回值,无效sql语句的时候会返回false,但如果输入sql语句时有效的...,仍然会返回有效的id,换句话说mysql_query无论是否查询值,,只要语法不出问题,都会返回真。...row = NULL 这个表达式的bool为假 { return true; } mysql_store_result():将mysql_query()查询到的结果集,...