# groonga - An open-source fulltext search engine and column store.

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# 7.3.39. `object_exist`

## 7.3.39.1. Summary

New in version 5.0.6.

`object_exist` returns whether object with the specified name exists or not in database.

It's a light operation. It just checks existence of the name in the database. It doesn't load the specified object from disk.

`object_exist` doesn't check object type. The existing object may be table, column, function and so on.

## 7.3.39.2. Syntax

This command takes only one required parameter:

    object_exist name

## 7.3.39.3. Usage

You can check whether the name is already used in database:

Execution example:

    object_exist Users
    # [[0, 1337566253.89858, 0.000355720520019531], false]
    table_create Users TABLE_HASH_KEY ShortText
    # [[0, 1337566253.89858, 0.000355720520019531], true]
    object_exist Users
    # [[0, 1337566253.89858, 0.000355720520019531], true]

The `object_exist Users` returns `false` before you create `Users` table.

The `object_exist Users` returns `true` after you create `Users` table.

## 7.3.39.4. Parameters

This section describes all parameters.

### 7.3.39.4.1. Required parameters

There is only one required parameters.

#### 7.3.39.4.1.1. `name`

Specifies the object name to be checked.

If you want to check existence of a column, use `TABLE_NAME.COLUMN_NAME` format like the following:

Execution example:

    table_create Logs TABLE_NO_KEY
    # [[0, 1337566253.89858, 0.000355720520019531], true]
    column_create Logs timestamp COLUMN_SCALAR Time
    # [[0, 1337566253.89858, 0.000355720520019531], true]
    object_exist Logs.timestamp
    # [[0, 1337566253.89858, 0.000355720520019531], true]

`Logs` is table name and `timestamp` is column name in `Logs.timestamp`.

### 7.3.39.4.2. Optional parameters

There is no optional parameter.

## 7.3.39.5. Return value

The command returns `true` as body if object with the specified name exists in database such as:

    [HEADER, true]

The command returns `false` otherwise such as:

    [HEADER, false]

See Output format for `HEADER`.