How do I replace NULLs with 0 in hive?

How do I replace NULLs with 0 in hive?

Use nvl() function in Hive to replace all NULL values of a column with a default value, In this article, I will explain with an example. Replace all NULL values with -1 or 0 or any number for the integer column. Replace all NULL values with empty space for string types. Replace with any value based on your need.

IS NULL function in hive?

2.1 isnull( a ) This returns a true when the value of a (column) is NULL otherwise it returns false. Above example column _C1 is derived based on salary column, if you notice isnull() function return true for value NULL and false for non NULL values.

Does NVL work in hive?

The hive nvl function is one of the same functions. We can use the nvl function as the keyword in the hive query. It will update, we need to replace the null value in the table with the specific value.

How do I drop a null partition in hive?

I tried the below syntax and its not working for me.. alter table “tablename” drop partition(partn=’_hive_default_partition_); alter table “tablename” drop partition(partn<‘1′); alter table “tablename” drop partition(partn = 1); alter table “tablename” drop partition(partn=’0’);

How do I change the default value in hive?

Hive currently doesn’t support the feature of adding default value to any column while creating table. As a workaround temporarily load data into temporary table and use the insert overwrite table statement to add the current date and time into the main table. create table final_table (sno number, createDate string);

How do you write if condition in hive?

Conditional Functions in Hive

1. IF( Test Condition, True Value, False Value ) The IF condition evaluates the “Test Condition” and if the “Test Condition” is true, then it returns the “True Value”.
2. COALESCE( value1,value2,… ) The COALESCE function returns the fist not NULL value from the list of values.
3. CASE Statement.

How do you write if else condition in hive?

Hive Conditional Functions Examples

1. Hive IF condition function example select IF(1=1,’TRUE’,’FALSE’) as IF_CONDITION_TEST;
2. Hive ISNULL condition function example select isnull( NULL );
3. Hive ISNOTNULL condition function example select isnotnull( NULL );
4. Hive CASE conditional function examples.

How do I count NULL values in Hive?

1. Query: select 2gusage,count(2gusage) from demo group by 2gusage; Output: MID 765153. HIGH 18095461. LOW 119069472.
2. NULL 25997075. I tried the below query to find the count of NULL values.
3. Query. select count(*) from demo where 2gusage is ‘NULL’; Output. Kindly help me out with the query to find the count of NULL values.

How do you write an if statement in Hive?

Syntax of If condition in Hive The if condition accepts exactly 3 arguments in Hive. Here we specify the condition as a first argument, Then we need to mention the true and false values as a second and third argument. It allows NULL as a value in the place of valueTrue/valueFalseorNull.

Which function is used to substitute for value if value is NULL?

ISNULL Function
The ISNULL Function is a built-in function to replace nulls with specified replacement values. To use this function, all you need to do is pass the column name in the first parameter and in the second parameter pass the value with which you want to replace the null value.