src/Pure/General/sql.scala
author wenzelm
Tue May 02 23:21:53 2017 +0200 (2017-05-02)
changeset 65691 2229276a1f99
parent 65690 74ec3cfcb6bf
child 65695 4edac706bc5e
permissions -rw-r--r--
eliminated redundant type SQL.View;
eliminated unused DROP operations;
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/*  Title:      Pure/General/sql.scala
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    Author:     Makarius
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Support for SQL databases: SQLite and PostgreSQL.
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*/
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package isabelle
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import java.time.OffsetDateTime
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import java.sql.{DriverManager, Connection, PreparedStatement, ResultSet}
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object SQL
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{
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  /** SQL language **/
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  /* concrete syntax */
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  def escape_char(c: Char): String =
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    c match {
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      case '\u0000' => "\\0"
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      case '\'' => "\\'"
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      case '\"' => "\\\""
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      case '\b' => "\\b"
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      case '\n' => "\\n"
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      case '\r' => "\\r"
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      case '\t' => "\\t"
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      case '\u001a' => "\\Z"
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      case '\\' => "\\\\"
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      case _ => c.toString
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    }
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  def string(s: String): String =
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    "'" + s.map(escape_char(_)).mkString + "'"
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  def identifer(s: String): String =
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    Long_Name.implode(Long_Name.explode(s).map(a => quote(a.replace("\"", "\"\""))))
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  def enclose(s: String): String = "(" + s + ")"
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  def enclosure(ss: Iterable[String]): String = ss.mkString("(", ", ", ")")
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  def select(columns: List[Column], distinct: Boolean = false): String =
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    "SELECT " + (if (distinct) "DISTINCT " else "") + commas(columns.map(_.sql)) + " FROM "
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  def join(table1: Table, table2: Table, sql: String = "", outer: Boolean = false): String =
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    table1.sql + (if (outer) " LEFT OUTER JOIN " else " INNER JOIN ") + table2.sql +
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      (if (sql == "") "" else " ON " + sql)
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  def join_outer(table1: Table, table2: Table, sql: String = ""): String =
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    join(table1, table2, sql, outer = true)
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  /* types */
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  object Type extends Enumeration
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  {
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    val Boolean = Value("BOOLEAN")
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    val Int = Value("INTEGER")
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    val Long = Value("BIGINT")
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    val Double = Value("DOUBLE PRECISION")
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    val String = Value("TEXT")
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    val Bytes = Value("BLOB")
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    val Date = Value("TIMESTAMP WITH TIME ZONE")
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  }
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  def sql_type_default(T: Type.Value): String = T.toString
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  def sql_type_sqlite(T: Type.Value): String =
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    if (T == Type.Boolean) "INTEGER"
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    else if (T == Type.Date) "TEXT"
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    else sql_type_default(T)
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  def sql_type_postgresql(T: Type.Value): String =
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    if (T == Type.Bytes) "BYTEA"
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    else sql_type_default(T)
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  /* columns */
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  object Column
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  {
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    def bool(name: String, strict: Boolean = false, primary_key: Boolean = false): Column =
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      Column(name, Type.Boolean, strict, primary_key)
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    def int(name: String, strict: Boolean = false, primary_key: Boolean = false): Column =
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      Column(name, Type.Int, strict, primary_key)
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    def long(name: String, strict: Boolean = false, primary_key: Boolean = false): Column =
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      Column(name, Type.Long, strict, primary_key)
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    def double(name: String, strict: Boolean = false, primary_key: Boolean = false): Column =
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      Column(name, Type.Double, strict, primary_key)
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    def string(name: String, strict: Boolean = false, primary_key: Boolean = false): Column =
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      Column(name, Type.String, strict, primary_key)
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    def bytes(name: String, strict: Boolean = false, primary_key: Boolean = false): Column =
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      Column(name, Type.Bytes, strict, primary_key)
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    def date(name: String, strict: Boolean = false, primary_key: Boolean = false): Column =
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      Column(name, Type.Date, strict, primary_key)
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  }
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  sealed case class Column(
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    name: String, T: Type.Value, strict: Boolean = false, primary_key: Boolean = false)
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  {
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    def apply(table: Table): Column =
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      Column(Long_Name.qualify(table.name, name), T, strict = strict, primary_key = primary_key)
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    def sql: String = identifer(name)
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    def sql_decl(sql_type: Type.Value => String): String =
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      identifer(name) + " " + sql_type(T) + (if (strict || primary_key) " NOT NULL" else "")
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    def sql_where_eq: String = "WHERE " + identifer(name) + " = "
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    def sql_where_equal(s: String): String = sql_where_eq + string(s)
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    override def toString: String = sql_decl(sql_type_default)
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  }
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  /* tables */
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  sealed case class Table(name: String, columns: List[Column], view: String = "")
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  {
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    private val columns_index: Map[String, Int] =
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      columns.iterator.map(_.name).zipWithIndex.toMap
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    Library.duplicates(columns.map(_.name)) match {
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      case Nil =>
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      case bad => error("Duplicate column names " + commas_quote(bad) + " for table " + quote(name))
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    }
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    def is_view: Boolean = view != ""
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    def sql: String = identifer(name)
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    def sql_columns(sql_type: Type.Value => String): String =
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    {
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      val primary_key =
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        columns.filter(_.primary_key).map(_.name) match {
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          case Nil => Nil
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          case keys => List("PRIMARY KEY " + enclosure(keys))
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        }
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      enclosure(columns.map(_.sql_decl(sql_type)) ::: primary_key)
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    }
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    def sql_create(strict: Boolean, sql_type: Type.Value => String): String =
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      "CREATE TABLE " + (if (strict) "" else "IF NOT EXISTS ") +
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        identifer(name) + " " + sql_columns(sql_type)
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    def sql_create_index(
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        index_name: String, index_columns: List[Column],
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        strict: Boolean, unique: Boolean): String =
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      "CREATE " + (if (unique) "UNIQUE " else "") + "INDEX " +
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        (if (strict) "" else "IF NOT EXISTS ") + identifer(index_name) + " ON " +
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        identifer(name) + " " + enclosure(index_columns.map(_.name))
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    def sql_insert: String =
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      "INSERT INTO " + identifer(name) + " VALUES " + enclosure(columns.map(_ => "?"))
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    def sql_delete: String =
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      "DELETE FROM " + identifer(name)
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    def sql_select(select_columns: List[Column], distinct: Boolean = false): String =
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      select(select_columns, distinct = distinct) + identifer(name)
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    override def toString: String =
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      "TABLE " + identifer(name) + " " + sql_columns(sql_type_default)
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  }
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  /** SQL database operations **/
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  /* results */
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  def iterator[A](rs: ResultSet)(get: ResultSet => A): Iterator[A] = new Iterator[A]
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  {
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    private var _next: Boolean = rs.next()
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    def hasNext: Boolean = _next
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    def next: A = { val x = get(rs); _next = rs.next(); x }
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  }
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  trait Database
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  {
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    /* types */
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    def sql_type(T: Type.Value): String
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    /* connection */
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    def connection: Connection
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    def close() { connection.close }
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    def transaction[A](body: => A): A =
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    {
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      val auto_commit = connection.getAutoCommit
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      try {
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        connection.setAutoCommit(false)
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        val savepoint = connection.setSavepoint
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        try {
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          val result = body
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          connection.commit
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          result
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        }
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        catch { case exn: Throwable => connection.rollback(savepoint); throw exn }
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      }
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      finally { connection.setAutoCommit(auto_commit) }
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    }
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    /* statements */
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    def statement(sql: String): PreparedStatement = connection.prepareStatement(sql)
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    def insert(table: Table): PreparedStatement = statement(table.sql_insert)
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    def delete(table: Table, sql: String = ""): PreparedStatement =
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      statement(table.sql_delete + (if (sql == "") "" else " " + sql))
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    def select(table: Table, columns: List[Column], sql: String = "", distinct: Boolean = false)
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        : PreparedStatement =
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      statement(table.sql_select(columns, distinct = distinct) + (if (sql == "") "" else " " + sql))
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    /* input */
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    def set_bool(stmt: PreparedStatement, i: Int, x: Boolean) { stmt.setBoolean(i, x) }
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    def set_bool(stmt: PreparedStatement, i: Int, x: Option[Boolean])
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    {
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      if (x.isDefined) set_bool(stmt, i, x.get)
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      else stmt.setNull(i, java.sql.Types.BOOLEAN)
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    }
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    def set_int(stmt: PreparedStatement, i: Int, x: Int) { stmt.setInt(i, x) }
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    def set_int(stmt: PreparedStatement, i: Int, x: Option[Int])
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    {
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      if (x.isDefined) set_int(stmt, i, x.get)
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      else stmt.setNull(i, java.sql.Types.INTEGER)
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    }
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    def set_long(stmt: PreparedStatement, i: Int, x: Long) { stmt.setLong(i, x) }
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    def set_long(stmt: PreparedStatement, i: Int, x: Option[Long])
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    {
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      if (x.isDefined) set_long(stmt, i, x.get)
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      else stmt.setNull(i, java.sql.Types.BIGINT)
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    }
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    def set_double(stmt: PreparedStatement, i: Int, x: Double) { stmt.setDouble(i, x) }
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    def set_double(stmt: PreparedStatement, i: Int, x: Option[Double])
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    {
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      if (x.isDefined) set_double(stmt, i, x.get)
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      else stmt.setNull(i, java.sql.Types.DOUBLE)
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    }
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    def set_string(stmt: PreparedStatement, i: Int, x: String) { stmt.setString(i, x) }
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    def set_string(stmt: PreparedStatement, i: Int, x: Option[String]): Unit =
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      set_string(stmt, i, x.orNull)
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    def set_bytes(stmt: PreparedStatement, i: Int, bytes: Bytes)
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    {
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      if (bytes == null) stmt.setBytes(i, null)
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      else stmt.setBinaryStream(i, bytes.stream(), bytes.length)
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    }
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    def set_bytes(stmt: PreparedStatement, i: Int, bytes: Option[Bytes]): Unit =
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      set_bytes(stmt, i, bytes.orNull)
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    def set_date(stmt: PreparedStatement, i: Int, date: Date): Unit
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    def set_date(stmt: PreparedStatement, i: Int, date: Option[Date]): Unit =
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      set_date(stmt, i, date.orNull)
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    /* output */
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    def bool(rs: ResultSet, column: Column): Boolean = rs.getBoolean(column.name)
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    def int(rs: ResultSet, column: Column): Int = rs.getInt(column.name)
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    def long(rs: ResultSet, column: Column): Long = rs.getLong(column.name)
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    def double(rs: ResultSet, column: Column): Double = rs.getDouble(column.name)
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    def string(rs: ResultSet, column: Column): String =
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    {
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      val s = rs.getString(column.name)
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      if (s == null) "" else s
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    }
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    def bytes(rs: ResultSet, column: Column): Bytes =
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    {
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      val bs = rs.getBytes(column.name)
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      if (bs == null) Bytes.empty else Bytes(bs)
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    }
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    def date(rs: ResultSet, column: Column): Date
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    def get[A](rs: ResultSet, column: Column, f: (ResultSet, Column) => A): Option[A] =
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    {
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      val x = f(rs, column)
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      if (rs.wasNull) None else Some(x)
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    }
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    /* tables and views */
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    def tables: List[String] =
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      iterator(connection.getMetaData.getTables(null, null, "%", null))(_.getString(3)).toList
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    def create_table(table: Table, strict: Boolean = false, sql: String = ""): Unit =
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      using(statement(table.sql_create(strict, sql_type) + (if (sql == "") "" else " " + sql)))(
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        _.execute())
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    def create_index(table: Table, name: String, columns: List[Column],
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        strict: Boolean = false, unique: Boolean = false): Unit =
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      using(statement(table.sql_create_index(name, columns, strict, unique)))(_.execute())
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    def create_view(table: Table, strict: Boolean = false): Unit =
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    {
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      require(table.is_view)
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      if (strict || !tables.contains(table.name)) {
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        val sql = "CREATE VIEW " + identifer(table.name) + " AS " + table.view
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        using(statement(sql))(_.execute())
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      }
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    }
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  }
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}
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/** SQLite **/
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object SQLite
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{
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  // see https://www.sqlite.org/lang_datefunc.html
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  val date_format: Date.Format = Date.Format("uuuu-MM-dd HH:mm:ss.SSS x")
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  lazy val init_jdbc: Unit = Class.forName("org.sqlite.JDBC")
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  def open_database(path: Path): Database =
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  {
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    init_jdbc
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    val path0 = path.expand
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    val s0 = File.platform_path(path0)
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    val s1 = if (Platform.is_windows) s0.replace('\\', '/') else s0
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    val connection = DriverManager.getConnection("jdbc:sqlite:" + s1)
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    new Database(path0.toString, connection)
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  }
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  class Database private[SQLite](name: String, val connection: Connection) extends SQL.Database
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  {
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    override def toString: String = name
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    def sql_type(T: SQL.Type.Value): String = SQL.sql_type_sqlite(T)
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    def set_date(stmt: PreparedStatement, i: Int, date: Date): Unit =
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      if (date == null) set_string(stmt, i, null: String)
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      else set_string(stmt, i, date_format(date))
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    def date(rs: ResultSet, column: SQL.Column): Date =
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      date_format.parse(string(rs, column))
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    def rebuild { using(statement("VACUUM"))(_.execute()) }
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  }
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}
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/** PostgreSQL **/
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object PostgreSQL
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{
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  val default_port = 5432
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  lazy val init_jdbc: Unit = Class.forName("org.postgresql.Driver")
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  def open_database(
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    user: String,
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    password: String,
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    database: String = "",
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    host: String = "",
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    port: Int = 0,
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    ssh: Option[SSH.Session] = None,
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    ssh_close: Boolean = false): Database =
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  {
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    init_jdbc
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    if (user == "") error("Undefined database user")
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    val db_host = if (host != "") host else "localhost"
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    val db_port = if (port > 0 && port != default_port) ":" + port else ""
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    val db_name = "/" + (if (database != "") database else user)
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    val (url, name, port_forwarding) =
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      ssh match {
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        case None =>
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          val spec = db_host + db_port + db_name
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          val url = "jdbc:postgresql://" + spec
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          val name = user + "@" + spec
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          (url, name, None)
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        case Some(ssh) =>
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          val fw =
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            ssh.port_forwarding(remote_host = db_host,
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              remote_port = if (port > 0) port else default_port,
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              ssh_close = ssh_close)
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          val url = "jdbc:postgresql://localhost:" + fw.local_port + db_name
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          val name = user + "@" + fw + db_name + " via ssh " + ssh
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          (url, name, Some(fw))
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      }
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    try {
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      val connection = DriverManager.getConnection(url, user, password)
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      new Database(name, connection, port_forwarding)
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    }
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    catch { case exn: Throwable => port_forwarding.foreach(_.close); throw exn }
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  }
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  class Database private[PostgreSQL](
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      name: String, val connection: Connection, port_forwarding: Option[SSH.Port_Forwarding])
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    extends SQL.Database
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  {
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    override def toString: String = name
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    def sql_type(T: SQL.Type.Value): String = SQL.sql_type_postgresql(T)
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    // see https://jdbc.postgresql.org/documentation/head/8-date-time.html
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    def set_date(stmt: PreparedStatement, i: Int, date: Date): Unit =
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      if (date == null) stmt.setObject(i, null)
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      else stmt.setObject(i, OffsetDateTime.from(date.to_utc.rep))
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    def date(rs: ResultSet, column: SQL.Column): Date =
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      Date.instant(rs.getObject(column.name, classOf[OffsetDateTime]).toInstant)
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    override def close() { super.close; port_forwarding.foreach(_.close) }
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  }
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}