Delete Predicate

The DelPred request deletes all entries from a store that match a specified predicate condition.

• Input: Store name and predicate condition.

• Behavior: Removes all entries whose metadata matches the predicate.

• Response: Confirmation of deletion with count of deleted entries.

Click to expand source code

import { createDbClient } from "ahnlich-client-node";
import { DelPred } from "ahnlich-client-node/grpc/db/query_pb";
import { PredicateCondition, Predicate, Equals } from "ahnlich-client-node/grpc/predicate_pb";
import { MetadataValue } from "ahnlich-client-node/grpc/metadata_pb";

async function deletePredicate() {
  const client = createDbClient("127.0.0.1:1369");

  const response = await client.delPred(
    new DelPred({
      store: "my_store",
      condition: new PredicateCondition({
        kind: {
          case: "value",
          value: new Predicate({
            kind: {
              case: "equals",
              value: new Equals({
                key: "status",
                value: new MetadataValue({ value: { case: "rawString", value: "archived" } }),
              }),
            },
          }),
        },
      }),
    })
  );

  console.log(`Deleted ${response.deleted} entries`);
}

deletePredicate();

Parameters

Parameter	Type	Required	Description
store	string	Yes	The name of the store
condition	PredicateCondition	Yes	The filter condition for deletion

Example with Complex Condition

Click to expand source code

import { createDbClient } from "ahnlich-client-node";
import { DelPred } from "ahnlich-client-node/grpc/db/query_pb";
import { 
  PredicateCondition, 
  Predicate, 
  Equals, 
  AndCondition 
} from "ahnlich-client-node/grpc/predicate_pb";
import { MetadataValue } from "ahnlich-client-node/grpc/metadata_pb";

async function deleteWithComplexCondition() {
  const client = createDbClient("127.0.0.1:1369");

  // Delete all archived items in category "temp"
  const response = await client.delPred(
    new DelPred({
      store: "my_store",
      condition: new PredicateCondition({
        kind: {
          case: "and",
          value: new AndCondition({
            left: new PredicateCondition({
              kind: {
                case: "value",
                value: new Predicate({
                  kind: {
                    case: "equals",
                    value: new Equals({
                      key: "status",
                      value: new MetadataValue({ value: { case: "rawString", value: "archived" } }),
                    }),
                  },
                }),
              },
            }),
            right: new PredicateCondition({
              kind: {
                case: "value",
                value: new Predicate({
                  kind: {
                    case: "equals",
                    value: new Equals({
                      key: "category",
                      value: new MetadataValue({ value: { case: "rawString", value: "temp" } }),
                    }),
                  },
                }),
              },
            }),
          }),
        },
      }),
    })
  );

  console.log(`Deleted ${response.deleted} archived temp entries`);
}

deleteWithComplexCondition();

Notes

• Use with caution - this operation permanently deletes data
• For deleting specific entries, use Delete Key
• Predicate indices improve the performance of predicate-based deletions