check_constraints.cc

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#include "sql/dd/impl/tables/check_constraints.h"

#include <new>

#include "sql/dd/impl/raw/object_keys.h"   // dd::Parent_id_range_key
#include "sql/dd/impl/raw/raw_record.h"    // dd::Raw_record
#include "sql/dd/impl/raw/raw_table.h"     // dd::Raw_table
#include "sql/dd/impl/transaction_impl.h"  // Transaction_ro
#include "sql/dd/impl/types/object_table_definition_impl.h"

namespace dd {
namespace tables {

///////////////////////////////////////////////////////////////////////////

const Check_constraints &Check_constraints::instance() {
  static Check_constraints *s_instance = new (std::nothrow) Check_constraints();
  return *s_instance;
}

///////////////////////////////////////////////////////////////////////////

const CHARSET_INFO *Check_constraints::name_collation() {
  return &my_charset_utf8mb3_tolower_ci;
}

///////////////////////////////////////////////////////////////////////////

Check_constraints::Check_constraints() {
  m_target_def.set_table_name("check_constraints");

  m_target_def.add_field(FIELD_ID, "FIELD_ID",
                         "id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT");
  m_target_def.add_field(FIELD_SCHEMA_ID, "FIELD_SCHEMA_ID",
                         "schema_id BIGINT UNSIGNED NOT NULL");
  m_target_def.add_field(FIELD_TABLE_ID, "FIELD_TABLE_ID",
                         "table_id BIGINT UNSIGNED NOT NULL");
  m_target_def.add_field(FIELD_NAME, "FIELD_NAME",
                         "name VARCHAR(64) NOT NULL COLLATE " +
                             String_type(name_collation()->m_coll_name));
  m_target_def.add_field(FIELD_ENFORCED, "FIELD_ENFORCED",
                         "enforced ENUM('NO', 'YES') NOT NULL");
  m_target_def.add_field(FIELD_CHECK_CLAUSE, "FIELD_CHECK_CLAUSE",
                         "check_clause LONGBLOB NOT NULL");
  m_target_def.add_field(FIELD_CHECK_CLAUSE_UTF8, "FIELD_CHECK_CLAUSE_UTF8",
                         "check_clause_utf8 LONGTEXT NOT NULL");

  m_target_def.add_index(INDEX_PK_ID, "INDEX_PK_ID", "PRIMARY KEY (id)");
  m_target_def.add_index(INDEX_UK_SCHEMA_ID_NAME, "INDEX_UK_SCHEMA_ID_NAME",
                         "UNIQUE KEY (schema_id, name)");
  m_target_def.add_index(INDEX_UK_TABLE_ID_NAME, "INDEX_UK_TABLE_ID_NAME",
                         "UNIQUE KEY (table_id, name)");

  m_target_def.add_foreign_key(FK_SCHEMA_ID, "FK_SCHEMA_ID",
                               "FOREIGN KEY (schema_id) REFERENCES "
                               "schemata(id)");
  m_target_def.add_foreign_key(FK_TABLE_ID, "FK_TABLE_ID",
                               "FOREIGN KEY (table_id) REFERENCES "
                               "tables(id)");
}

///////////////////////////////////////////////////////////////////////////

Object_key *Check_constraints::create_key_by_table_id(Object_id table_id) {
  return new (std::nothrow)
      Parent_id_range_key(INDEX_UK_TABLE_ID_NAME, FIELD_TABLE_ID, table_id);
}

///////////////////////////////////////////////////////////////////////////

Object_key *Check_constraints::create_key_by_check_constraint_name(
    Object_id schema_id, const String_type &check_cons_name) {
  return new (std::nothrow)
      Item_name_key(FIELD_SCHEMA_ID, schema_id, FIELD_NAME, check_cons_name,
                    name_collation());
}

///////////////////////////////////////////////////////////////////////////

bool Check_constraints::check_constraint_exists(
    THD *thd, Object_id schema_id, const String_type &check_cons_name,
    bool *exists) {
  DBUG_TRACE;

  Transaction_ro trx(thd, ISO_READ_COMMITTED);
  trx.otx.register_tables<dd::Check_constraint>();
  if (trx.otx.open_tables()) return true;

  const std::unique_ptr<Object_key> key(
      create_key_by_check_constraint_name(schema_id, check_cons_name.c_str()));

  Raw_table *table = trx.otx.get_table(instance().name());
  assert(table != nullptr);

  // Find record by the object-key.
  std::unique_ptr<Raw_record> record;
  if (table->find_record(*key, record)) return true;

  if (record.get())
    *exists = true;
  else
    *exists = false;

  return false;
}

///////////////////////////////////////////////////////////////////////////

}  // namespace tables
}  // namespace dd