# nullIf

**Syntax**

nullIf(X, Y)

**Arguments**

X / Y can be a scalar or vector, or an expression that returns a scalar or vector.

**Details**

For two scalars, the function returns a NULL value if the values and data types of

*X*and*Y*are equal. Otherwise, returns*X*.For two vectors of equal length, the function conducts the aforementioned calculation with each pair of elements in

*X*and*Y*at the same position.For a scalar and a vector, the function conducts the aforementioned calculation on the scalar and each element of the vector.

**Examples**

```
$ t = table(`APPL`IBM`AMZN`IBM`APPL`AMZN as sym, 10.1 11.2 11.3 12 10.6 10.8 as val)
$ select nullIf(sym, `AMZN) from t
```

nullIf_sym |
---|

APPL |

IBM |

IBM |

APPL |

```
$ select * from t where nullIf(sym, `AMZN)!=NULL
```

sym | val |
---|---|

APPL | 10.1 |

IBM | 11.2 |

IBM | 12 |

APPL | 10.6 |