Initial commit

Author: feliposz

.gitattributes

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+* text=auto

.gitignore

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+*.db

README.md

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+![progress-banner](https://codecrafters.io/landing/images/default_progress_banners/sqlite.png)
+
+This is a starting point for Go 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 `app/main.go`. Study and
+uncomment the relevant code, and push your changes to pass the first stage:
+
+```sh
+git add .
+git commit -m "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 `go (1.16+)` installed locally
+1. Run `./your_sqlite3.sh` to run your program, which is implemented in
+   `app/main.go`.
+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).

app/main.go

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+package main
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"log"
+	"os"
+	// Available if you need it!
+	// "github.com/xwb1989/sqlparser"
+)
+
+// Usage: your_sqlite3.sh sample.db .dbinfo
+func main() {
+	databaseFilePath := os.Args[1]
+	command := os.Args[2]
+
+	switch command {
+	case ".dbinfo":
+		databaseFile, err := os.Open(databaseFilePath)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		header := make([]byte, 100)
+
+		_, err = databaseFile.Read(header)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		var pageSize uint16
+		if err := binary.Read(bytes.NewReader(header[16:18]), binary.BigEndian, &pageSize); err != nil {
+			fmt.Println("Failed to read integer:", err)
+			return
+		}
+		// You can use print statements as follows for debugging, they'll be visible when running tests.
+		fmt.Println("Logs from your program will appear here!")
+
+		// Uncomment this to pass the first stage
+		// fmt.Printf("database page size: %v", pageSize)
+	default:
+		fmt.Println("Unknown command", command)
+		os.Exit(1)
+	}
+}

codecrafters.yml

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+# 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 Go version used to run your code
+# on Codecrafters.
+#
+# Available versions: go-1.22
+language_pack: go-1.22

download_sample_databases.sh

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+#!/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."

go.mod

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+// DON'T EDIT THIS!
+//
+// Codecrafters relies on this file being intact to run tests successfully. Any changes
+// here will not reflect when CodeCrafters tests your code, and might even cause build
+// failures.
+//
+// DON'T EDIT THIS!
+
+module github/com/codecrafters-io/sqlite-starter-go
+
+go 1.22
+
+require github.com/xwb1989/sqlparser v0.0.0-20180606152119-120387863bf2

go.sum

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+github.com/xwb1989/sqlparser v0.0.0-20180606152119-120387863bf2 h1:zzrxE1FKn5ryBNl9eKOeqQ58Y/Qpo3Q9QNxKHX5uzzQ=
+github.com/xwb1989/sqlparser v0.0.0-20180606152119-120387863bf2/go.mod h1:hzfGeIUDq/j97IG+FhNqkowIyEcD88LrW6fyU3K3WqY=

your_sqlite3.sh

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+#!/bin/sh
+#
+# DON'T EDIT THIS!
+#
+# CodeCrafters uses this file to test your code. Don't make any changes here!
+#
+# DON'T EDIT THIS!
+set -e
+tmpFile=$(mktemp)
+go build -o "$tmpFile" $(dirname "$0")/app/*.go
+exec "$tmpFile" "$@"