druvu-lib-jdbc

SQL first. Write the statement, bind the parameters, map the row. A thin layer over Spring JDBC where the SQL stays in view instead of behind an ORM.

Spring JDBC comes along as a dependency. Published to GitHub Packages, which needs a one-time token to read. See Install.

View on GitHub

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Try it

DbConfig config = DbConfig.of("myDb",
    "jdbc:postgresql://localhost/mydb", "user", "pass",
    "org.postgresql.Driver", "SELECT 1");
DbAccess db = DbAccessFactory.create(config);

List<Map<String, Object>> users = db.select(
    SimpleSql.fromString("SELECT * FROM users WHERE status = ?").with("active"));

Optional<Map<String, Object>> user = db.selectOne(
    SimpleSql.fromString("SELECT * FROM users WHERE id = ?").with(userId));

Named parameters, and a row mapped to your own type:

Optional<User> user = db.selectOne(
    SimpleSql.named("SELECT * FROM users WHERE id = :id")
        .with("id", userId)
        .map((rs, rowNum) -> new User(rs.getInt("id"), rs.getString("name"))));

Two statements in one transaction:

db.runInTransaction(tx -> {
    tx.update(SimpleSql.fromString("UPDATE accounts SET balance = balance - ? WHERE id = ?").with(amount, fromAccount));
    tx.update(SimpleSql.fromString("UPDATE accounts SET balance = balance + ? WHERE id = ?").with(amount, toAccount));
});

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What you get

• positional ? and named :param parameters, bound fluently
• SQL from a string, a class-path resource or a file; %s includes compose one file from others
• ??? expands to as many ? as the collection has: an IN clause without string glue
• lambda row mappers; selectOne returns an Optional and throws on more than one row, selectFirst takes the first
• rows streamed one at a time for large results
• transactions with or without a return value; toDebugString() shows the SQL with its values filled in

One thing to know: a loaded SQL file that contains %s is processed as a format string, so a literal % followed by s (LIKE '%smith') must be written %%. Better, pass LIKE patterns as parameters.

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Install (GitHub Packages)

Java 21 or newer. GitHub Packages needs Maven authentication even for a public package. Once per machine: a token with the read:packages scope and a server entry in ~/.m2/settings.xml:

<servers>
  <server>
    <id>github</id>
    <username>YOUR_GITHUB_USERNAME</username>
    <password>YOUR_GITHUB_TOKEN</password>
  </server>
</servers>

Then in the project:

<repositories>
    <repository>
        <id>github</id>
        <url>https://maven.pkg.github.com/DenissLarka/druvu-lib-jdbc</url>
    </repository>
</repositories>

<dependency>
    <groupId>com.druvu</groupId>
    <artifactId>druvu-lib-jdbc</artifactId>
    <version>1.0.0</version>
</dependency>

The full reference, every statement form and the utilities, is the README.

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Something it almost does?

Open an issue, or write to me. If it is small and useful to more than you, I will often just build it.

Apache License 2.0.