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v0.1.0 ... main

Author SHA1 Message Date
29d1784813 add authors comment 2024-05-07 00:35:28 +03:00
1cd6f44af8 fix issues 2024-05-07 00:34:35 +03:00
97934dd5ac Merge branch 'jorenchik-main' 2024-05-07 00:31:40 +03:00
f3345f7cc1 fix: skill issue 2024-05-07 00:31:13 +03:00
Kristofers Solo
f6128287ad Create LICENSE 2024-05-07 00:31:13 +03:00
1bf92654da chore: add actions
add main file
2024-05-07 00:31:13 +03:00
3f4261e918 minor changes 2024-05-07 00:31:13 +03:00
928bd8554f refactor: use columns 2024-05-07 00:31:07 +03:00
jorenchik
a9bb553cf3 export 2024-05-06 22:59:41 +03:00
jorenchik
226bf240d6 fix seeks 2024-05-06 22:59:26 +03:00
a78da83197 fix: skill issue 2024-05-06 22:35:59 +03:00
jorenchik
5f19876f7a minor fixes 2024-05-06 22:11:48 +03:00
Kristofers Solo
31dbb38511
Create LICENSE 2024-05-06 22:08:40 +03:00
3 changed files with 39 additions and 6 deletions

21
LICENSE Normal file
View File

@ -0,0 +1,21 @@
MIT License
Copyright (c) 2024 Kristofers Solo
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

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export/DB2Cheatsheet.pdf Normal file

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@ -26,7 +26,7 @@ to 1 indicating presence or true, and a bit set to 0 indicating absence or
columns: 2, gutter: 2em, tablex(
stroke: 0.5pt, columns: 2, colspanx(2)[Bitmaps for `gender`], `m`, `10010`, `f`, `01101`,
), tablex(
stroke: 0.5pt, columns: 2, colspanx(2)[Bitmaps for `income_level`], `L1`, `10010`, `L2`, `01000`, `L3`, `00001`, `L4`, `00010`, `L5`, `00000`,
stroke: 0.5pt, columns: 2, colspanx(2)[Bitmaps for `income_level`], `L1`, `10100`, `L2`, `01000`, `L3`, `00001`, `L4`, `00010`, `L5`, `00000`,
),
)
@ -87,9 +87,10 @@ Simplified version (to get the idea)
for each tuple tr in r: (for each tuple ts in s: test pair (tr, ts))
```
// TODO: Add seek information
Block transfer cost: $n_r dot b_s + b_r$ block transfers would be required,
where $b_r$ -- blocks in relation $r$, same for $s$.
where $b_r$ -- blocks in relation $r$, same for $s$. Each scan of the inner
relation requires one seek, and the scan of the outer relation requires one seek
per block, leading to a total of $2 dot b_r$ seeks.
== Block-nested join
@ -275,7 +276,8 @@ The concept of conflict equivalence leads to the concept of conflict
serializability. We say that a schedule $S$ is *conflict serializable* if it is
conflict equivalent to a serial schedule.
=== Serializability graph
// TODO: rename to precedence
=== Precedence graph
Simple and efficient method for determining the conflict seriazability of a
schedule. Consider a schedule $S$. We construct a directed graph, called a
@ -310,6 +312,15 @@ locking protocol. We say that a locking protocol ensures conflict
serializability if and only if all legal schedules are *conflict serializable*;
in other words, for all legal schedules the associated $->$ relation is acyclic.
*Recoverable* schedule is one where, for each pair of transactions $T_i$ and
$T_j$ such that $T_j$ reads a data item previously written by $T_i$, the commit
operation of $T_i$ appears before the commit operation of $T_j$.
*Cascadeless* schedule is one where, for each pair of transactions $T_i$ and
$T_j$ such that $T_j$ reads a data item previously written by $T_i$, the commit
operation of $T_i$ appears before the read operation of $T_j$. Every cascadeless
schedule is also recoverable.
=== Lock-based
*Shared Lock* -- If a transaction $T_i$ has obtained a shared-mode lock (denoted
@ -475,7 +486,8 @@ $B=5;T_"disk"=0.001;T_"seek"=0.1$
=== Nested-Loop Join Method
+ Nested-loop join:
- For each pattern in $r_1$, search all patterns in $r_2$.
+ Total Combinations: $75435 dot 11456=$
+ Total Combinations: $75435 dot 11456$
+ Time Calculation for Nested-Loop Join:
- Reading and searching time for each combination: $0.001+0.1=0.101 "ms"$
- Total time: $75435 dot 11456 dot 0.101 = 87282519.36 "ms"$
- Total time: $75435 dot 11456 dot 0.101 = 87282519.36 "ms"$ [Authors comment:
seems fishy]