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WITH RECURSIVE search_graph(id, link, data, depth, path, cycle) AS (
        SELECT g.id, g.link, g.data, 1,
          ARRAY[g.id],
          false
        FROM graph g
      UNION ALL
        SELECT g.id, g.link, g.data, sg.depth + 1,
          path || g.id,
          g.id = ANY(path)
        FROM graph g, search_graph sg

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BEGIN;
  LOCK TABLE new_table IN ACCESS EXCLUSIVE MODE;

  CREATE TABLE new_table_clean AS 
    (SELECT DISTINCT ON(column1, column2) * FROM new_table);
  
  TRUNCATE TABLE new_table;

  INSERT INTO new_table SELECT * FROM new_table_clean;
END;

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CREATE OR REPLACE FUNCTION some_function(some_ids UUID[])
  RETURNS TABLE (id INTEGER)
  LANGUAGE SQL
AS $$

-- ERROR: function some_function(record[]) does not exist

CREATE OR REPLACE FUNCTION some_function(VARIADIC some_ids UUID[])
  RETURNS TABLE (id INTEGER)
  LANGUAGE SQL

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-- Source: https://www.cybertec-postgresql.com/
SELECT
  relname, seq_scan, seq_tup_read,
  idx_scan, idx_tup_fetch,
  seq_tup_read / seq_scan
FROM pg_stat_user_tables
WHERE seq_scan > 0 AND schemaname='myschema'
ORDER BY seq_tup_read DESC;

-- Richtige Einfügereihenfolge: https://www.cybertec-postgresql.com/en/postgresql-foreign-keys-and-insertion-order-in-sql/

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List<Integer> nodeIds = session.createSQLQuery("SELECT get_graph(3)").list();

MultiIdentifierLoadAccess<NodesEntity> multiLoadAccess = session.byMultipleIds(NodesEntity.class);
List<NodesEntity> nodes = multiLoadAccess.multiLoad(nodeIds);

for (NodesEntity node:nodes) {
    System.out.println(node.getNodeName());

    for(EdgesEntity edge : node.edges) {
        System.out.println(String.format("   %s (%d) -> %s (%d) %s",

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CREATE INDEX edges_from_node_id_to_node_id_idx ON playground.edges(from_node_id,to_node_id);

INSERT INTO playground.nodes (node_name) VALUES(chr(generate_series(65,75))); -- A..K
INSERT INTO playground.edges (from_node_id, to_node_id, type)
  VALUES
    (1,2,'parent'),(2,3,'parent'),(3,1,'parent'),(3,10,'parent'),(10,3,'child'),
    (7,8,'parent'),(8,7,'child');
  
  
CREATE OR REPLACE FUNCTION get_graph(node_id INTEGER)

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@Entity
@Table(name = "nodes", schema = "playground", catalog = "postgres")
public class NodesEntity {
    @Id
    @Column(name = "id", nullable = false)
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;

    @Basic
    @Column(name = "node_name", nullable = false, length = 10)

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CREATE SCHEMA IF NOT EXISTS playground;

DROP TABLE IF EXISTS playground.edges;
DROP TABLE IF EXISTS playground.nodes;

CREATE TABLE playground.nodes
(
    id SERIAL PRIMARY KEY,
    node_name VARCHAR(10) NOT NULL
);

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version: "3.1"

services:
  db:
    image: postgres
    command: ["postgres", "-c", "logging_collector=on", "-c", "log_directory=/var/log/postgresql", "-c", "log_filename=postgresql.log", "-c", "log_statement=all"]
    restart: always
    environment:
      POSTGRES_PASSWORD: postgres
    volumes:

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internal sealed class PhoneBook {
  private String m_pathname; // path name of file containing the address book
  
  // Other methods go here.
  public String GetPhoneNumber(String name) {
    String phone;
    FileStream fs = null;
    try {
      fs = new FileStream(m_pathname, FileMode.Open);
      // Code to read from fs until name is found goes here