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11 changes: 11 additions & 0 deletions compiled_starters/scala/.codecrafters/compile.sh
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#!/bin/sh
#
# This script is used to compile your program on CodeCrafters
#
# This runs before .codecrafters/run.sh
#
# Learn more: https://codecrafters.io/program-interface

set -e # Exit on failure

sbt assembly
11 changes: 11 additions & 0 deletions compiled_starters/scala/.codecrafters/run.sh
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
#!/bin/sh
#
# This script is used to run your program on CodeCrafters
#
# This runs after .codecrafters/compile.sh
#
# Learn more: https://codecrafters.io/program-interface

set -e # Exit on failure

exec java -jar ./target/scala-3.3.5/sqlite.jar "$@"
1 change: 1 addition & 0 deletions compiled_starters/scala/.gitattributes
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@@ -0,0 +1 @@
* text=auto
10 changes: 10 additions & 0 deletions compiled_starters/scala/.gitignore
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@@ -0,0 +1,10 @@
# Database files used for testing
*.db

**/target
/.bloop/
/.bsp/
/.metals/
/project/.bloop/
metals.sbt
metals/project/
77 changes: 77 additions & 0 deletions compiled_starters/scala/README.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,77 @@
![progress-banner](https://codecrafters.io/landing/images/default_progress_banners/sqlite.png)

This is a starting point for Scala solutions to the
["Build Your Own SQLite" Challenge](https://codecrafters.io/challenges/sqlite).

In this challenge, you'll build a barebones SQLite implementation that supports
basic SQL queries like `SELECT`. Along the way we'll learn about
[SQLite's file format](https://www.sqlite.org/fileformat.html), how indexed data
is
[stored in B-trees](https://jvns.ca/blog/2014/10/02/how-does-sqlite-work-part-2-btrees/)
and more.

**Note**: If you're viewing this repo on GitHub, head over to
[codecrafters.io](https://codecrafters.io) to try the challenge.

# Passing the first stage

The entry point for your SQLite implementation is in
`src/main/scala/Main.scala`. Study and uncomment the relevant code, and push
your changes to pass the first stage:

```sh
git commit -am "pass 1st stage" # any msg
git push origin master
```

Time to move on to the next stage!

# Stage 2 & beyond

Note: This section is for stages 2 and beyond.

1. Ensure you have `sbt (1.10.7)` installed locally
1. Run `./your_program.sh` to run your program, which is implemented in
`src/main/scala/Main.scala`.
1. Commit your changes and run `git push origin master` to submit your solution
to CodeCrafters. Test output will be streamed to your terminal.

# Sample Databases

To make it easy to test queries locally, we've added a sample database in the
root of this repository: `sample.db`.

This contains two tables: `apples` & `oranges`. You can use this to test your
implementation for the first 6 stages.

You can explore this database by running queries against it like this:

```sh
$ sqlite3 sample.db "select id, name from apples"
1|Granny Smith
2|Fuji
3|Honeycrisp
4|Golden Delicious
```

There are two other databases that you can use:

1. `superheroes.db`:
- This is a small version of the test database used in the table-scan stage.
- It contains one table: `superheroes`.
- It is ~1MB in size.
1. `companies.db`:
- This is a small version of the test database used in the index-scan stage.
- It contains one table: `companies`, and one index: `idx_companies_country`
- It is ~7MB in size.

These aren't included in the repository because they're large in size. You can
download them by running this script:

```sh
./download_sample_databases.sh
```

If the script doesn't work for some reason, you can download the databases
directly from
[codecrafters-io/sample-sqlite-databases](https://github.com/codecrafters-io/sample-sqlite-databases).
14 changes: 14 additions & 0 deletions compiled_starters/scala/build.sbt
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ThisBuild / scalaVersion := "3.3.5"
ThisBuild / version := "0.1.0-SNAPSHOT"
ThisBuild / organization := "com.CodeCrafters"
ThisBuild / organizationName := "CodeCrafters"

assembly / assemblyJarName := "sqlite"

lazy val root = (project in file("."))
.settings(
name := "codecrafter-sqlite",
// List your dependencies here
libraryDependencies ++= Seq(
),
)
11 changes: 11 additions & 0 deletions compiled_starters/scala/codecrafters.yml
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
# Set this to true if you want debug logs.
#
# These can be VERY verbose, so we suggest turning them off
# unless you really need them.
debug: false

# Use this to change the Scala version used to run your code
# on Codecrafters.
#
# Available versions: scala-3.3.5
language_pack: scala-3.3.5
9 changes: 9 additions & 0 deletions compiled_starters/scala/download_sample_databases.sh
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@@ -0,0 +1,9 @@
#!/bin/sh

echo "Downloading superheroes.db: ~1MB (used in stage 7)"
curl -Lo superheroes.db https://raw.githubusercontent.com/codecrafters-io/sample-sqlite-databases/master/superheroes.db

echo "Downloading companies.db: ~7MB (used in stage 8)"
curl -Lo companies.db https://raw.githubusercontent.com/codecrafters-io/sample-sqlite-databases/master/companies.db

echo "Sample databases downloaded."
1 change: 1 addition & 0 deletions compiled_starters/scala/project/build.properties
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@@ -0,0 +1 @@
sbt.version=1.10.7
3 changes: 3 additions & 0 deletions compiled_starters/scala/project/plugins.sbt
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@@ -0,0 +1,3 @@


addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "2.3.1")
Binary file added compiled_starters/scala/sample.db
Binary file not shown.
37 changes: 37 additions & 0 deletions compiled_starters/scala/src/main/scala/Main.scala
Original file line number Diff line number Diff line change
@@ -0,0 +1,37 @@
import java.io.File
import java.io.FileInputStream
import java.io.IOException
import java.nio.ByteBuffer
import scala.util.Using

object Main extends App {
if args.length < 2
then {
println("Missing <database path> and <command>")
System.exit(0);
}
val databaseFilePath = args(0);
val command = args(1);
command match {
case ".dbinfo" => {
Using(new FileInputStream(new File(databaseFilePath))) { databaseFile =>
databaseFile.skip(16)
val pageSizeBytes = new Array[Byte](2)
databaseFile.read(pageSizeBytes)
val pageSizeSigned = ByteBuffer.wrap(pageSizeBytes).getShort()
val pageSize = pageSizeSigned & 0xFFFF

// You can use print statements as follows for debugging, they'll be visible when running tests.
System.err.println("Logs from your program will appear here!")

// Uncomment this block to pass the first stage
// println("database page size: " + pageSize)
}.recover {
case e: IOException =>
println(s"Error reading database file: ${e.getMessage}")
System.exit(1)
}
}
case _ => println("Missing or invalid command passed: " + command)
}
}
24 changes: 24 additions & 0 deletions compiled_starters/scala/your_program.sh
Original file line number Diff line number Diff line change
@@ -0,0 +1,24 @@
#!/bin/sh
#
# Use this script to run your program LOCALLY.
#
# Note: Changing this script WILL NOT affect how CodeCrafters runs your program.
#
# Learn more: https://codecrafters.io/program-interface

set -e # Exit early if any commands fail

# Copied from .codecrafters/compile.sh
#
# - Edit this to change how your program compiles locally
# - Edit .codecrafters/compile.sh to change how your program compiles remotely
(
cd "$(dirname "$0")" # Ensure compile steps are run within the repository directory
sbt assembly
)

# Copied from .codecrafters/run.sh
#
# - Edit this to change how your program runs locally
# - Edit .codecrafters/run.sh to change how your program runs remotely
exec java -jar ./target/scala-3.3.5/sqlite.jar "$@"
19 changes: 19 additions & 0 deletions dockerfiles/scala-3.3.5.Dockerfile
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# syntax=docker/dockerfile:1.7-labs
FROM maven:3.9.9-eclipse-temurin-23-alpine

RUN apk add --no-cache bash wget tar && \
wget -O sbt.tgz https://github.com/sbt/sbt/releases/download/v1.10.11/sbt-1.10.11.tgz && \
tar -xzf sbt.tgz -C /usr/local && \
ln -s /usr/local/sbt/bin/sbt /usr/local/bin/sbt && \
rm sbt.tgz

# Ensures the container is re-built if dependency files change
ENV CODECRAFTERS_DEPENDENCY_FILE_PATHS="build.sbt"

WORKDIR /app

# .git & README.md are unique per-repository. We ignore them on first copy to prevent cache misses
COPY --exclude=.git --exclude=README.md . /app
Comment on lines +15 to +16
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🛠️ Refactor suggestion

Invalid Flag in COPY Command

The COPY instruction is using --exclude flags, which are not supported in Dockerfile COPY commands. To exclude files like .git and README.md from being copied, use a .dockerignore file. For example, create a .dockerignore file at the repository root with the following entries:

.git
README.md

Then modify the COPY command to simply copy the directory:

- COPY --exclude=.git --exclude=README.md . /app
+ COPY . /app
🧰 Tools
🪛 Hadolint (2.12.0)

[error] 16-16: invalid flag: --exclude

(DL1000)


# Install language-specific dependencies
RUN .codecrafters/compile.sh
11 changes: 11 additions & 0 deletions solutions/scala/01-dr6/code/.codecrafters/compile.sh
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
#!/bin/sh
#
# This script is used to compile your program on CodeCrafters
#
# This runs before .codecrafters/run.sh
#
# Learn more: https://codecrafters.io/program-interface

set -e # Exit on failure

sbt assembly
11 changes: 11 additions & 0 deletions solutions/scala/01-dr6/code/.codecrafters/run.sh
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
#!/bin/sh
#
# This script is used to run your program on CodeCrafters
#
# This runs after .codecrafters/compile.sh
#
# Learn more: https://codecrafters.io/program-interface

set -e # Exit on failure

exec java -jar ./target/scala-3.3.5/sqlite.jar "$@"
1 change: 1 addition & 0 deletions solutions/scala/01-dr6/code/.gitattributes
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
* text=auto
10 changes: 10 additions & 0 deletions solutions/scala/01-dr6/code/.gitignore
Original file line number Diff line number Diff line change
@@ -0,0 +1,10 @@
# Database files used for testing
*.db

**/target
/.bloop/
/.bsp/
/.metals/
/project/.bloop/
metals.sbt
metals/project/
77 changes: 77 additions & 0 deletions solutions/scala/01-dr6/code/README.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,77 @@
![progress-banner](https://codecrafters.io/landing/images/default_progress_banners/sqlite.png)

This is a starting point for Scala solutions to the
["Build Your Own SQLite" Challenge](https://codecrafters.io/challenges/sqlite).

In this challenge, you'll build a barebones SQLite implementation that supports
basic SQL queries like `SELECT`. Along the way we'll learn about
[SQLite's file format](https://www.sqlite.org/fileformat.html), how indexed data
is
[stored in B-trees](https://jvns.ca/blog/2014/10/02/how-does-sqlite-work-part-2-btrees/)
and more.

**Note**: If you're viewing this repo on GitHub, head over to
[codecrafters.io](https://codecrafters.io) to try the challenge.

# Passing the first stage

The entry point for your SQLite implementation is in
`src/main/scala/Main.scala`. Study and uncomment the relevant code, and push
your changes to pass the first stage:

```sh
git commit -am "pass 1st stage" # any msg
git push origin master
```

Time to move on to the next stage!

# Stage 2 & beyond

Note: This section is for stages 2 and beyond.

1. Ensure you have `sbt (1.10.7)` installed locally
1. Run `./your_program.sh` to run your program, which is implemented in
`src/main/scala/Main.scala`.
1. Commit your changes and run `git push origin master` to submit your solution
to CodeCrafters. Test output will be streamed to your terminal.

# Sample Databases

To make it easy to test queries locally, we've added a sample database in the
root of this repository: `sample.db`.

This contains two tables: `apples` & `oranges`. You can use this to test your
implementation for the first 6 stages.

You can explore this database by running queries against it like this:

```sh
$ sqlite3 sample.db "select id, name from apples"
1|Granny Smith
2|Fuji
3|Honeycrisp
4|Golden Delicious
```

There are two other databases that you can use:

1. `superheroes.db`:
- This is a small version of the test database used in the table-scan stage.
- It contains one table: `superheroes`.
- It is ~1MB in size.
1. `companies.db`:
- This is a small version of the test database used in the index-scan stage.
- It contains one table: `companies`, and one index: `idx_companies_country`
- It is ~7MB in size.

These aren't included in the repository because they're large in size. You can
download them by running this script:

```sh
./download_sample_databases.sh
```

If the script doesn't work for some reason, you can download the databases
directly from
[codecrafters-io/sample-sqlite-databases](https://github.com/codecrafters-io/sample-sqlite-databases).
14 changes: 14 additions & 0 deletions solutions/scala/01-dr6/code/build.sbt
Original file line number Diff line number Diff line change
@@ -0,0 +1,14 @@
ThisBuild / scalaVersion := "3.3.5"
ThisBuild / version := "0.1.0-SNAPSHOT"
ThisBuild / organization := "com.CodeCrafters"
ThisBuild / organizationName := "CodeCrafters"

assembly / assemblyJarName := "sqlite"

lazy val root = (project in file("."))
.settings(
name := "codecrafter-sqlite",
// List your dependencies here
libraryDependencies ++= Seq(
),
)
11 changes: 11 additions & 0 deletions solutions/scala/01-dr6/code/codecrafters.yml
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
# Set this to true if you want debug logs.
#
# These can be VERY verbose, so we suggest turning them off
# unless you really need them.
debug: false

# Use this to change the Scala version used to run your code
# on Codecrafters.
#
# Available versions: scala-3.3.5
language_pack: scala-3.3.5
9 changes: 9 additions & 0 deletions solutions/scala/01-dr6/code/download_sample_databases.sh
Original file line number Diff line number Diff line change
@@ -0,0 +1,9 @@
#!/bin/sh

echo "Downloading superheroes.db: ~1MB (used in stage 7)"
curl -Lo superheroes.db https://raw.githubusercontent.com/codecrafters-io/sample-sqlite-databases/master/superheroes.db

echo "Downloading companies.db: ~7MB (used in stage 8)"
curl -Lo companies.db https://raw.githubusercontent.com/codecrafters-io/sample-sqlite-databases/master/companies.db

echo "Sample databases downloaded."
1 change: 1 addition & 0 deletions solutions/scala/01-dr6/code/project/build.properties
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
sbt.version=1.10.7
Loading