我需要进度条或状态消息来显示执行查询时间。现在我的应用程序只冻结，我无法显示已经过了多少时间以及查询执行的位置（执行与检索）
我对此没有太多了解，而且我不知道它是否可能因为冻结，是否有办法取消查询？
谢谢！
答案 0 :(得分：1)
要在执行长时间运行的查询时拥有未冻结的应用程序，您需要在单独的线程上执行它。尝试使用 Rules useless in parser due to conflicts
7 expr: simp_expr relop simp_expr
9 simp_expr: simp_expr addop term
11 term: term mulop factor
16 factor: not factor
State 12 conflicts: 1 shift/reduce
State 13 conflicts: 2 shift/reduce
State 14 conflicts: 1 shift/reduce
State 17 conflicts: 2 reduce/reduce
State 20 conflicts: 6 reduce/reduce
State 25 conflicts: 1 shift/reduce
State 26 conflicts: 2 shift/reduce, 6 reduce/reduce
State 27 conflicts: 1 shift/reduce, 6 reduce/reduce
State 28 conflicts: 6 reduce/reduce
Grammar
0 $accept: stmt_list $end
1 stmt_list: stmt
2 | stmt_list ';' stmt
3 stmt: var assignop expr
4 var: id
5 | id '[' expr ']'
6 expr: simp_expr
7 | simp_expr relop simp_expr
8 simp_expr: term
9 | simp_expr addop term
10 term: factor
11 | term mulop factor
12 factor: id
13 | num
14 | expr
15 | id '[' expr ']'
16 | not factor
Terminals, with rules where they appear
$end (0) 0
';' (59) 2
'[' (91) 5 15
']' (93) 5 15
error (256)
id (258) 4 5 12 15
num (259) 13
relop (260) 7
mulop (261) 11
addop (262) 9
assignop (263) 3
not (264) 16
Nonterminals, with rules where they appear
$accept (13)
on left: 0
stmt_list (14)
on left: 1 2, on right: 0 2
stmt (15)
on left: 3, on right: 1 2
var (16)
on left: 4 5, on right: 3
expr (17)
on left: 6 7, on right: 3 5 14 15
simp_expr (18)
on left: 8 9, on right: 6 7 9
term (19)
on left: 10 11, on right: 8 9 11
factor (20)
on left: 12 13 14 15 16, on right: 10 11 16
state 0
0 $accept: . stmt_list $end
1 stmt_list: . stmt
2 | . stmt_list ';' stmt
3 stmt: . var assignop expr
4 var: . id
5 | . id '[' expr ']'
id shift, and go to state 1
stmt_list go to state 2
stmt go to state 3
var go to state 4
state 1
4 var: id . [assignop]
5 | id . '[' expr ']'
'[' shift, and go to state 5
$default reduce using rule 4 (var)
state 2
0 $accept: stmt_list . $end
2 stmt_list: stmt_list . ';' stmt
$end shift, and go to state 6
';' shift, and go to state 7
state 3
1 stmt_list: stmt .
$default reduce using rule 1 (stmt_list)
state 4
3 stmt: var . assignop expr
assignop shift, and go to state 8
state 5
5 var: id '[' . expr ']'
6 expr: . simp_expr
7 | . simp_expr relop simp_expr
8 simp_expr: . term
9 | . simp_expr addop term
10 term: . factor
11 | . term mulop factor
12 factor: . id
13 | . num
14 | . expr
15 | . id '[' expr ']'
16 | . not factor
id shift, and go to state 9
num shift, and go to state 10
not shift, and go to state 11
expr go to state 12
simp_expr go to state 13
term go to state 14
factor go to state 15
state 6
0 $accept: stmt_list $end .
$default accept
state 7
2 stmt_list: stmt_list ';' . stmt
3 stmt: . var assignop expr
4 var: . id
5 | . id '[' expr ']'
id shift, and go to state 1
stmt go to state 16
var go to state 4
state 8
3 stmt: var assignop . expr
6 expr: . simp_expr
7 | . simp_expr relop simp_expr
8 simp_expr: . term
9 | . simp_expr addop term
10 term: . factor
11 | . term mulop factor
12 factor: . id
13 | . num
14 | . expr
15 | . id '[' expr ']'
16 | . not factor
id shift, and go to state 9
num shift, and go to state 10
not shift, and go to state 11
expr go to state 17
simp_expr go to state 13
term go to state 14
factor go to state 15
state 9
12 factor: id . [$end, relop, mulop, addop, ';', ']']
15 | id . '[' expr ']'
'[' shift, and go to state 18
$default reduce using rule 12 (factor)
state 10
13 factor: num .
$default reduce using rule 13 (factor)
state 11
6 expr: . simp_expr
7 | . simp_expr relop simp_expr
8 simp_expr: . term
9 | . simp_expr addop term
10 term: . factor
11 | . term mulop factor
12 factor: . id
13 | . num
14 | . expr
15 | . id '[' expr ']'
16 | . not factor
16 | not . factor
id shift, and go to state 9
num shift, and go to state 10
not shift, and go to state 11
expr go to state 19
simp_expr go to state 13
term go to state 14
factor go to state 20
state 12
5 var: id '[' expr . ']'
14 factor: expr . [relop, mulop, addop, ']']
']' shift, and go to state 21
']' [reduce using rule 14 (factor)]
$default reduce using rule 14 (factor)
state 13
6 expr: simp_expr . [$end, relop, mulop, addop, ';', ']']
7 | simp_expr . relop simp_expr
9 simp_expr: simp_expr . addop term
relop shift, and go to state 22
addop shift, and go to state 23
relop [reduce using rule 6 (expr)]
addop [reduce using rule 6 (expr)]
$default reduce using rule 6 (expr)
state 14
8 simp_expr: term . [$end, relop, mulop, addop, ';', ']']
11 term: term . mulop factor
mulop shift, and go to state 24
mulop [reduce using rule 8 (simp_expr)]
$default reduce using rule 8 (simp_expr)
state 15
10 term: factor .
$default reduce using rule 10 (term)
state 16
2 stmt_list: stmt_list ';' stmt .
$default reduce using rule 2 (stmt_list)
state 17
3 stmt: var assignop expr . [$end, ';']
14 factor: expr . [$end, relop, mulop, addop, ';']
$end reduce using rule 3 (stmt)
$end [reduce using rule 14 (factor)]
';' reduce using rule 3 (stmt)
';' [reduce using rule 14 (factor)]
$default reduce using rule 14 (factor)
state 18
6 expr: . simp_expr
7 | . simp_expr relop simp_expr
8 simp_expr: . term
9 | . simp_expr addop term
10 term: . factor
11 | . term mulop factor
12 factor: . id
13 | . num
14 | . expr
15 | . id '[' expr ']'
15 | id '[' . expr ']'
16 | . not factor
id shift, and go to state 9
num shift, and go to state 10
not shift, and go to state 11
expr go to state 25
simp_expr go to state 13
term go to state 14
factor go to state 15
state 19
14 factor: expr .
$default reduce using rule 14 (factor)
state 20
10 term: factor . [$end, relop, mulop, addop, ';', ']']
16 factor: not factor . [$end, relop, mulop, addop, ';', ']']
$end reduce using rule 10 (term)
$end [reduce using rule 16 (factor)]
relop reduce using rule 10 (term)
relop [reduce using rule 16 (factor)]
mulop reduce using rule 10 (term)
mulop [reduce using rule 16 (factor)]
addop reduce using rule 10 (term)
addop [reduce using rule 16 (factor)]
';' reduce using rule 10 (term)
';' [reduce using rule 16 (factor)]
']' reduce using rule 10 (term)
']' [reduce using rule 16 (factor)]
$default reduce using rule 10 (term)
state 21
5 var: id '[' expr ']' .
$default reduce using rule 5 (var)
state 22
6 expr: . simp_expr
7 | . simp_expr relop simp_expr
7 | simp_expr relop . simp_expr
8 simp_expr: . term
9 | . simp_expr addop term
10 term: . factor
11 | . term mulop factor
12 factor: . id
13 | . num
14 | . expr
15 | . id '[' expr ']'
16 | . not factor
id shift, and go to state 9
num shift, and go to state 10
not shift, and go to state 11
expr go to state 19
simp_expr go to state 26
term go to state 14
factor go to state 15
state 23
6 expr: . simp_expr
7 | . simp_expr relop simp_expr
8 simp_expr: . term
9 | . simp_expr addop term
9 | simp_expr addop . term
10 term: . factor
11 | . term mulop factor
12 factor: . id
13 | . num
14 | . expr
15 | . id '[' expr ']'
16 | . not factor
id shift, and go to state 9
num shift, and go to state 10
not shift, and go to state 11
expr go to state 19
simp_expr go to state 13
term go to state 27
factor go to state 15
state 24
6 expr: . simp_expr
7 | . simp_expr relop simp_expr
8 simp_expr: . term
9 | . simp_expr addop term
10 term: . factor
11 | . term mulop factor
11 | term mulop . factor
12 factor: . id
13 | . num
14 | . expr
15 | . id '[' expr ']'
16 | . not factor
id shift, and go to state 9
num shift, and go to state 10
not shift, and go to state 11
expr go to state 19
simp_expr go to state 13
term go to state 14
factor go to state 28
state 25
14 factor: expr . [relop, mulop, addop, ']']
15 | id '[' expr . ']'
']' shift, and go to state 29
']' [reduce using rule 14 (factor)]
$default reduce using rule 14 (factor)
state 26
6 expr: simp_expr . [$end, relop, mulop, addop, ';', ']']
7 | simp_expr . relop simp_expr
7 | simp_expr relop simp_expr . [$end, relop, mulop, addop, ';', ']']
9 simp_expr: simp_expr . addop term
relop shift, and go to state 22
addop shift, and go to state 23
$end reduce using rule 6 (expr)
$end [reduce using rule 7 (expr)]
relop [reduce using rule 6 (expr)]
relop [reduce using rule 7 (expr)]
mulop reduce using rule 6 (expr)
mulop [reduce using rule 7 (expr)]
addop [reduce using rule 6 (expr)]
addop [reduce using rule 7 (expr)]
';' reduce using rule 6 (expr)
';' [reduce using rule 7 (expr)]
']' reduce using rule 6 (expr)
']' [reduce using rule 7 (expr)]
$default reduce using rule 6 (expr)
state 27
8 simp_expr: term . [$end, relop, mulop, addop, ';', ']']
9 | simp_expr addop term . [$end, relop, mulop, addop, ';', ']']
11 term: term . mulop factor
mulop shift, and go to state 24
$end reduce using rule 8 (simp_expr)
$end [reduce using rule 9 (simp_expr)]
relop reduce using rule 8 (simp_expr)
relop [reduce using rule 9 (simp_expr)]
mulop [reduce using rule 8 (simp_expr)]
mulop [reduce using rule 9 (simp_expr)]
addop reduce using rule 8 (simp_expr)
addop [reduce using rule 9 (simp_expr)]
';' reduce using rule 8 (simp_expr)
';' [reduce using rule 9 (simp_expr)]
']' reduce using rule 8 (simp_expr)
']' [reduce using rule 9 (simp_expr)]
$default reduce using rule 8 (simp_expr)
state 28
10 term: factor . [$end, relop, mulop, addop, ';', ']']
11 | term mulop factor . [$end, relop, mulop, addop, ';', ']']
$end reduce using rule 10 (term)
$end [reduce using rule 11 (term)]
relop reduce using rule 10 (term)
relop [reduce using rule 11 (term)]
mulop reduce using rule 10 (term)
mulop [reduce using rule 11 (term)]
addop reduce using rule 10 (term)
addop [reduce using rule 11 (term)]
';' reduce using rule 10 (term)
';' [reduce using rule 11 (term)]
']' reduce using rule 10 (term)
']' [reduce using rule 11 (term)]
$default reduce using rule 10 (term)
state 29
15 factor: id '[' expr ']' .
$default reduce using rule 15 (factor)
。它可以使用BackgroundWorker。有两种情况：
1 - 您有一个查询可以批量修改某个表，但它在DB服务器上运行很长时间。在这种情况下，如果可能，您可以（并且此处也有多个方案），将批处理日志写入某个表。您可以创建临时触发器和临时表查询目标表。触发器将在处理记录时更新临时表。在后台工作程序中编写SQL查询以查询临时表并查看记录的行数。这样做直到工作标记为＆＃34; DONE＆＃34; （在同一个临时表中）
2 - 在这种情况下，很容易跟踪进度，因为在这里您在代码中执行了一行SQL。所以你知道你有多少更新，并且可以精确地告诉你，例如＆＃34;处理5和1000＃34;。在您的后台工作人员中，您将在ReportProgress中完成此项工作，并且在每次拨打数据电话时，您都会调用DoWork。
如何实施ReportProgress您可以在线找到1000个示例。对于场景＃2，这几乎就是它。对于场景＃1，它取决于您的操作。可能有10种不同的方法来实现它。但主要逻辑仍然存在 - 一个单独的线程正在跟踪进度抛出一些设备（在本例中为表）。