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fix missing cast when simplify set stmt

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obdev 2023-09-14 03:10:17 +00:00 committed by ob-robot
parent a1e6b1c440
commit 0c6b823cc8
3 changed files with 62 additions and 68 deletions
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120
src/sql/rewrite/ob_transform_simplify_set.cpp
View File

@ -724,76 +724,68 @@ int ObTransformSimplifySet::replace_set_stmt_with_child_stmt(ObSelectStmt *&pare
ObSelectStmt *child_stmt)
{
int ret = OB_SUCCESS;
if (OB_ISNULL(parent_stmt) || OB_ISNULL(child_stmt)) {
if (OB_ISNULL(parent_stmt) || OB_ISNULL(child_stmt) || OB_ISNULL(ctx_) || OB_ISNULL(ctx_->expr_factory_)) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get null pointer", K(ret));
} else {
if ((parent_stmt->has_order_by() && (child_stmt->has_order_by() || child_stmt->has_limit()))
|| (parent_stmt->has_limit() && child_stmt->has_limit())
|| (parent_stmt->is_set_distinct() && child_stmt->has_limit())
|| (parent_stmt->has_select_into() && child_stmt->has_select_into())) {
/* 1. for limit clause
* if both parent_stmt and child_stmt has limit, we should create a view to hold parent's limit.
*
* 2. for add_order_by, child stmt shouldn't have order_by_items or limit items.
* if we meet conflict order by items. We can't directly reset child's order by.
* e.g., select * from t1 order by c1 limit 2 UNION ALL select * from t2 where 1=2 order by c2;
* if we overwrite the order by, the result is not correct.
*
* 3. for distinct.
* if child stmt has limit, we can't add distinct to child stmt. Since limit should be done before distinct.
*
* 4. select into is not allowed in subquery, we add the code here to handle conflict select into.
* just in case of some transformer rule generating conflict select into.
*/
ObSelectStmt *view_stmt = NULL;
if (OB_FAIL(ObTransformUtils::create_stmt_with_generated_table(ctx_, child_stmt, view_stmt))) {
LOG_WARN("fail to create view with generated table", K(ret));
} else if (OB_ISNULL(view_stmt)) {
LOG_WARN("view table is null", K(ret));
} else if (OB_FAIL(add_order_by(view_stmt, parent_stmt))) {
// set child's order by to view.
LOG_WARN("fail to assign parents's order items to child", K(ret));
} else {
//set child's limit to view. and reset child's order by items.
view_stmt->set_fetch_info(parent_stmt->get_offset_expr(),
parent_stmt->get_limit_expr(),
parent_stmt->get_limit_percent_expr());
if (parent_stmt->is_set_distinct()) {
view_stmt->assign_distinct();
}
if (parent_stmt->has_select_into()) {
view_stmt->set_select_into(parent_stmt->get_select_into());
}
parent_stmt = view_stmt;
}
/* 1. for limit clause
* if both parent_stmt and child_stmt has limit, we should create a view to hold parent's limit.
*
* 2. for add_order_by, child stmt shouldn't have order_by_items or limit items.
* if we meet conflict order by items. We can't directly reset child's order by.
* e.g., select * from t1 order by c1 limit 2 UNION ALL select * from t2 where 1=2 order by c2;
* if we overwrite the order by, the result is not correct.
*
* 3. for distinct.
* if child stmt has limit, we can't add distinct to child stmt. Since limit should be done before distinct.
*
* 4. select into is not allowed in subquery, we add the code here to handle conflict select into.
* just in case of some transformer rule generating conflict select into.
*/
ObSelectStmt *view_stmt = NULL;
if (OB_FAIL(ObTransformUtils::create_stmt_with_generated_table(ctx_, child_stmt, view_stmt))) {
LOG_WARN("fail to create view with generated table", K(ret));
} else if (OB_ISNULL(view_stmt)) {
LOG_WARN("view table is null", K(ret));
} else if (OB_FAIL(add_order_by(view_stmt, parent_stmt))) {
// set child's order by to view.
LOG_WARN("fail to assign parents's order items to child", K(ret));
} else {
/* order by clause*/
if (parent_stmt->has_order_by()) {
if (OB_FAIL(add_order_by(child_stmt, parent_stmt))) {
LOG_WARN("fail to assign parents's order items to child", K(ret));
// set child's limit to view. and reset child's order by items.
view_stmt->set_fetch_info(parent_stmt->get_offset_expr(),
parent_stmt->get_limit_expr(),
parent_stmt->get_limit_percent_expr());
if (parent_stmt->is_set_distinct()) {
view_stmt->assign_distinct();
}
if (parent_stmt->has_select_into()) {
view_stmt->set_select_into(parent_stmt->get_select_into());
}
// if the result type of the view stmt's projection expr does not match that of the parent set stmt
// cast expr need to be added to view's select items
if (OB_SUCC(ret) && OB_UNLIKELY(view_stmt->get_select_item_size() != parent_stmt->get_select_item_size())) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("select item size missmatch", K(ret));
} else {
for (int64_t i = 0; OB_SUCC(ret) && i < view_stmt->get_select_item_size(); i++) {
ObRawExpr *expr1 = parent_stmt->get_select_item(i).expr_;
ObRawExpr *expr2 = view_stmt->get_select_item(i).expr_;
if (OB_ISNULL(expr1) || OB_ISNULL(expr2)) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("unexpected null pointer", K(ret), KP(expr1), KP(expr2));
} else {
if (OB_FAIL(ObTransformUtils::add_cast_for_replace_if_need(*(ctx_->expr_factory_),
expr1,
expr2,
ctx_->session_info_))) {
LOG_WARN("fail to add cast expr for replace", K(ret));
} else {
view_stmt->get_select_item(i).expr_ = expr2;
}
}
}
}
if (OB_SUCC(ret) && parent_stmt->is_set_distinct()) {
if (child_stmt->is_set_stmt()) {
child_stmt->assign_set_distinct();
} else {
child_stmt->assign_distinct();
}
}
if (OB_SUCC(ret) && parent_stmt->has_select_into()) {
child_stmt->set_select_into(parent_stmt->get_select_into());
}
/*limit clause*/
if (OB_SUCC(ret) && parent_stmt->has_limit()) {
child_stmt->set_fetch_info(parent_stmt->get_offset_expr(),
parent_stmt->get_limit_expr(),
parent_stmt->get_limit_percent_expr());
}
parent_stmt = child_stmt;
parent_stmt = view_stmt;
}
}

6
src/sql/rewrite/ob_transform_utils.cpp
View File

@ -4352,11 +4352,13 @@ int ObTransformUtils::add_cast_for_replace_if_need(ObRawExprFactory &expr_factor
} else {
const ObExprResType &src_type = from_expr->get_result_type();
const ObExprResType &dst_type = to_expr->get_result_type();
bool need_length_cast = (ob_is_string_or_lob_type(dst_type.get_type()) || ob_is_rowid_tc(dst_type.get_type()))
? (src_type.get_length() != dst_type.get_length()) : false;
bool need_cast = (src_type.get_type() != dst_type.get_type()) ||
(src_type.get_length() != dst_type.get_length()) ||
(src_type.get_precision() != dst_type.get_precision()) ||
(src_type.get_scale() != dst_type.get_scale()) ||
from_expr->get_result_type().has_result_flag(ZEROFILL_FLAG);
from_expr->get_result_type().has_result_flag(ZEROFILL_FLAG) ||
need_length_cast;
if (ob_is_string_or_lob_type(src_type.get_type())) {
need_cast |= (src_type.get_collation_type() != dst_type.get_collation_type()) ||
(src_type.get_collation_level() != dst_type.get_collation_level());

4
tools/deploy/mysql_test/test_suite/transformer/r/mysql/transformer_predicate_deduce.result
View File

@ -3955,7 +3955,7 @@ Outputs & filters:
-------------------------------------
0 - output([v0.v1]), filter(nil), rowset=16
conds(nil), nl_params_(nil), use_batch=false
1 - output([v0.v1]), filter([v0.v1 = cast(cast(-127, VARCHAR(20)), VARCHAR(1048576))]), rowset=16
1 - output([v0.v1]), filter([v0.v1 = cast(cast(-127, VARCHAR(20)), VARCHAR(20))]), rowset=16
access([v0.v1]), partitions(p0)
is_index_back=false, is_global_index=false, filter_before_indexback[false],
range_key([v0.__pk_increment]), range(MIN ; MAX)always true
@ -3984,7 +3984,7 @@ Outputs & filters:
-------------------------------------
0 - output([v0.v1]), filter(nil), rowset=16
conds(nil), nl_params_(nil), use_batch=false
1 - output([v0.v1]), filter([v0.v1 = cast(cast(-127, VARCHAR(20)), VARCHAR(1048576))]), rowset=16
1 - output([v0.v1]), filter([v0.v1 = cast(cast(-127, VARCHAR(20)), VARCHAR(20))]), rowset=16
access([v0.v1]), partitions(p0)
is_index_back=false, is_global_index=false, filter_before_indexback[false],
range_key([v0.__pk_increment]), range(MIN ; MAX)always true