refactor: clean preview code

[DSFans2014]

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SDK Test Report

102 files  ±0  102 suites  ±0   2m 10s ⏱️ +5s
359 tests ±0  345 ✅ ±0  14 💤 ±0  0 ❌ ±0 
487 runs  ±0  473 ✅ ±0  14 💤 ±0  0 ❌ ±0 

Results for commit f2b23b2. ± Comparison against base commit b48326a.

This pull request removes 48 and adds 27 tests. Note that renamed tests count towards both.

  PARTITION BY db1.t1.col2 ORDER BY db1.t1.col1
  PARTITION BY t1.col2 ORDER BY t1.col1
  ROWS_RANGE BETWEEN 3 PRECEDING AND CURRENT ROW
 ) limit 10;](1)
 ) limit 10;](2)
 ) limit 10;](3)
 FROM db1.t1
 FROM t1
 WINDOW w1 AS (
 last join db2.t2 order by db2.t2.col1
…

com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlLastJoinWithMultipleDB[,  SELECT sum(db1.t1.col1) over w1 as sum_t1_col1, db2.t2.str1 as t2_str1
 FROM db1.t1
 last join db2.t2 order by db2.t2.col1
 on db1.t1.col1 = db2.t2.col1 and db1.t1.col2 = db2.t2.col0
 WINDOW w1 AS (
  PARTITION BY db1.t1.col2 ORDER BY db1.t1.col1
  ROWS_RANGE BETWEEN 3 PRECEDING AND CURRENT ROW
 ) limit 10;](2)
com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlLastJoinWithMultipleDB[db1,  SELECT sum(t1.col1) over w1 as sum_t1_col1, db2.t2.str1 as t2_str1
 FROM t1
 last join db2.t2 order by db2.t2.col1
 on t1.col1 = db2.t2.col1 and t1.col2 = db2.t2.col0
 WINDOW w1 AS (
  PARTITION BY t1.col2 ORDER BY t1.col1
  ROWS_RANGE BETWEEN 3 PRECEDING AND CURRENT ROW
 ) limit 10;](1)
com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlLastJoinWithMultipleDB[null,  SELECT sum(db1.t1.col1) over w1 as sum_t1_col1, db2.t2.str1 as t2_str1
 FROM db1.t1
 last join db2.t2 order by db2.t2.col1
 on db1.t1.col1 = db2.t2.col1 and db1.t1.col2 = db2.t2.col0
 WINDOW w1 AS (
  PARTITION BY db1.t1.col2 ORDER BY db1.t1.col1
  ROWS_RANGE BETWEEN 3 PRECEDING AND CURRENT ROW
 ) limit 10;](3)
com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlMultipleDBErrorTest[, SELECT db2.t2.str1 as t2_str1
 FROM t1
 last join db2.t2 order by db2.t2.col1
 on t1.col1 = db2.t2.col1 and t1.col2 = db2.t2.col0;
, SQL parse error: Fail to transform data provider op: table t1 not exists in database []](4)
com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlMultipleDBErrorTest[db1, SELECT db1.t2.str1 as t2_str1
 FROM t1
 last join db2.t2 order by db2.t2.col1
 on t1.col1 = db2.t2.col1 and t1.col2 = db2.t2.col0;
, SQL parse error: Column Not found: db1.t2.str1](2)
com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlMultipleDBErrorTest[db1, SELECT db2.t2.str1 as t2_str1
 FROM t1
 last join db2.t2 order by db2.t2.col1
 on t1.col1 = t2.col1 and t1.col2 = db2.t2.col0;
, SQL parse error: Column Not found: .t2.col1](3)
com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlMultipleDBErrorTest[db1, SELECT t2.str1 as t2_str1
 FROM t1
 last join db2.t2 order by db2.t2.col1
 on t1.col1 = db2.t2.col1 and t1.col2 = db2.t2.col0;
, SQL parse error: Column Not found: .t2.str1](1)
com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlMultipleDBErrorTest[null, SELECT db2.t2.str1 as t2_str1
 FROM t1
 last join db2.t2 order by db2.t2.col1
 on t1.col1 = db2.t2.col1 and t1.col2 = db2.t2.col0;
, SQL parse error: Fail to transform data provider op: table t1 not exists in database []](5)
com._4paradigm.hybridse.sdk.SqlEngineTest ‑ sqlWindowLastJoin[ SELECT sum(t1.col1) over w1 as sum_t1_col1, t2.str1 as t2_str1
 FROM t1
 last join t2 order by t2.col1
 on t1.col1 = t2.col1 and t1.col2 = t2.col0
 WINDOW w1 AS (
  PARTITION BY t1.col2 ORDER BY t1.col1
  ROWS_RANGE BETWEEN 3 PRECEDING AND CURRENT ROW
 ) limit 10;](1)
com._4paradigm.openmldb.jdbc.SQLRouterSmokeTest ‑ testInsertMeta[com._4paradigm.openmldb.sdk.impl.SqlClusterExecutor@5274830e](2)
…

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.31%. Comparing base (b48326a) to head (f2b23b2).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #4100      +/-   ##
============================================
+ Coverage     75.30%   75.31%   +0.01%     
  Complexity      711      711              
============================================
  Files           763      763              
  Lines        143738   143738              
  Branches       2017     2017              
============================================
+ Hits         108243   108261      +18     
+ Misses        35192    35174      -18     
  Partials        303      303              

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