Add sqlite support

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/repository/config/DialectResolver.java

@@ -32,11 +32,7 @@
 import org.springframework.data.jdbc.core.dialect.JdbcMySqlDialect;
 import org.springframework.data.jdbc.core.dialect.JdbcPostgresDialect;
 import org.springframework.data.jdbc.core.dialect.JdbcSqlServerDialect;
-import org.springframework.data.relational.core.dialect.Dialect;
-import org.springframework.data.relational.core.dialect.H2Dialect;
-import org.springframework.data.relational.core.dialect.HsqlDbDialect;
-import org.springframework.data.relational.core.dialect.MariaDbDialect;
-import org.springframework.data.relational.core.dialect.OracleDialect;
+import org.springframework.data.relational.core.dialect.*;
 import org.springframework.data.relational.core.sql.IdentifierProcessing;
 import org.springframework.data.util.Optionals;
 import org.springframework.jdbc.core.ConnectionCallback;
@@ -121,6 +117,9 @@ private static Dialect getDialect(Connection connection) throws SQLException {
 			if (name.contains("h2")) {
 				return H2Dialect.INSTANCE;
 			}
+			if (name.contains("sqlite")) {
+				return SQLiteDialect.INSTANCE;
+			}
 			if (name.contains("mysql")) {
 				return new JdbcMySqlDialect(getIdentifierProcessing(metaData));
 			}

spring-data-r2dbc/src/main/java/org/springframework/data/r2dbc/dialect/DialectResolver.java

@@ -33,6 +33,7 @@
  * resolution uses Spring's {@link SpringFactoriesLoader spring.factories} to determine available extensions.
  *
  * @author Mark Paluch
+ * @author Rudolf Schmidt
  * @see R2dbcDialect
  * @see SpringFactoriesLoader
  */

spring-data-relational/src/main/java/org/springframework/data/relational/core/dialect/SQLiteDialect.java

@@ -0,0 +1,96 @@
+package org.springframework.data.relational.core.dialect;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.data.convert.ReadingConverter;
+import org.springframework.data.convert.WritingConverter;
+import org.springframework.data.relational.core.sql.LockOptions;
+
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.time.ZoneOffset;
+import java.util.ArrayList;
+import java.util.Collection;
+
+/**
+ * SQL Dialect for SQLite.
+ *
+ * @author Rudolf Schmidt
+ * @since 3.3.0
+ */
+public class SQLiteDialect extends AbstractDialect {
+
+	public static final SQLiteDialect INSTANCE = new SQLiteDialect();
+
+	private SQLiteDialect() {
+	}
+
+	@Override
+	public LimitClause limit() {
+		return new LimitClause() {
+			@Override
+			public String getLimit(final long limit) {
+				return String.format("limit %d", limit);
+			}
+
+			@Override
+			public String getOffset(final long offset) {
+				throw new UnsupportedOperationException("offset alone not supported");
+			}
+
+			@Override
+			public String getLimitOffset(final long limit, final long offset) {
+				return String.format("limit %d offset %d", limit, offset);
+			}
+
+			@Override
+			public Position getClausePosition() {
+				return Position.AFTER_ORDER_BY;
+			}
+		};
+	}
+
+	@Override
+	public LockClause lock() {
+		return new LockClause() {
+			@Override
+			public String getLock(final LockOptions lockOptions) {
+				return "with lock";
+			}
+
+			@Override
+			public Position getClausePosition() {
+				return Position.AFTER_ORDER_BY;
+			}
+		};
+	}
+
+	@Override
+	public Collection<Object> getConverters() {
+		final var converters = new ArrayList<>(super.getConverters());
+		converters.add(LocalDateTimeToNumericConverter.INSTANCE);
+		converters.add(NumericToLocalDateTimeConverter.INSTANCE);
+		return converters;
+	}
+
+	@WritingConverter
+	private enum LocalDateTimeToNumericConverter implements Converter<LocalDateTime, Long> {
+
+		INSTANCE;
+
+		@Override
+		public Long convert(final LocalDateTime source) {
+			return source.atZone(ZoneOffset.UTC).toInstant().toEpochMilli();
+		}
+	}
+
+	@ReadingConverter
+	private enum NumericToLocalDateTimeConverter implements Converter<Long, LocalDateTime> {
+
+		INSTANCE;
+
+		@Override
+		public LocalDateTime convert(final Long source) {
+			return Instant.ofEpochMilli(source).atZone(ZoneOffset.UTC).toLocalDateTime();
+		}
+	}
+}