How do I get special characters in Hive?

Hive: How To Find Invisible Characters
  1. to find the position of the first tab in the line using instr.
  2. to find all rows that contain a tab character anywhere in the line, using the like expression with the SQL wildcard ‘%’

How do I create a Hive table with text formatting?

The general syntax for creating a table in Hive is: CREATE [EXTERNAL] TABLE [IF NOT EXISTS] [db_name.] table_name (col_name data_type [COMMENT ‘col_comment’],, …) [COMMENT ‘table_comment’] [ROW FORMAT row_format] [FIELDS TERMINATED BY char] [STORED AS file_format];

How do I create a table type in Hive?

In the Hive shell, get an extended description of the table. For example: DESCRIBE EXTENDED mydatabase. mytable; Scroll to the bottom of the command output to see the table type.

How do I change the Ascii character in Hive?

Try this: select REGEXP_REPLACE(‘”Persi és Levon Cnatówóeez’, ‘[^a-zA-Z0-9\u00E0-\u00FC ]+’, ”); I tried it on Hive and it replaces any character that is not a letter (a-zA-Z) a number (0-9) or an accented character (\u00E0-\u00FC).

How do I create a Hive table from a CSV file?

Create a Hive External Table – Example
  1. Step 1: Prepare the Data File. Create a CSV file titled ‘countries.csv’: sudo nano countries.csv. …
  2. Step 2: Import the File to HDFS. Create an HDFS directory. …
  3. Step 3: Create an External Table.

How would you create and manage the databases and tables using Hive?

Hive – Create Table
  1. Syntax. CREATE [TEMPORARY] [EXTERNAL] TABLE [IF NOT EXISTS] [db_name.] …
  2. Example. Let us assume you need to create a table named employee using CREATE TABLE statement. …
  3. JDBC Program. The JDBC program to create a table is given example. …
  4. Output. Table employee created. …
  5. Syntax. …
  6. Example. …
  7. JDBC Program. …
  8. Output:

What is Regexp_replace in Hive?

Hive REGEXP_REPLACE Function

Searches a string for a regular expression pattern and replaces every occurrence of the pattern with the specified replacement.

How do I change the backslash in Hive?

Use 4 backslashes: select regexp_replace(name_string,’\\\\”‘,'”‘) from t; Only backslash needs escaping. In Java and in regex the backslash has special meaning and needs escaping.

What is Rlike in Hive?

RLIKE (Right-Like) is a special function in Hive where if any substring of A matches with B then it evaluates to true. It also obeys Java regular expression pattern. Users don’t need to put % symbol for a simple match in RLIKE.

What is Concat_ws in Hive?

CONCAT_WS() stands for Concatenate With Separator and is a special form of CONCAT() . The first argument is the separator for the rest of the arguments. The separator is added between the strings to be concatenated. The separator can be a string, as can the rest of the arguments.

What is translate in Hive?

The Hive translate function translates the input string by replacing the characters present in the from string with the corresponding characters in the to string. This is similar to the translate function in PostgreSQL.

What is Regexp_extract?

Returns the first matching substring in the target value which matches the regular expression pattern.

What is the difference between the concat function and the Concat_ws function?

Both CONCAT() and CONCAT_WS() functions are used to concatenate two or more strings but the basic difference between them is that CONCAT_WS() function can do the concatenation along with a separator between strings, whereas in CONCAT() function there is no concept of the separator.

What is coalesce in hive?

COALESCE allows you to use other data from other fields as a proxy. For the first subject, you have their actual birthday. For the second subject, you have their first day of kindergarten. For the third subject, you have the day they registered with the lord of the manor.

How do I use the cast function in hive?

Hive CAST(from_datatype as to_datatype) function is used to convert from one data type to another for example to cast String to Integer(int), String to Bigint, String to Decimal, Decimal to Int data types, and many more.

What is the difference between concat and Group_concat in MySQL?

The difference here is while CONCAT is used to combine values across columns, GROUP_CONCAT gives you the capability to combine values across rows. It’s also important to note that both GROUP_CONCAT and CONCAT can be combined to return desired results.

What is Group_concat in MySQL?

The GROUP_CONCAT() function in MySQL is used to concatenate data from multiple rows into one field. This is an aggregate (GROUP BY) function which returns a String value, if the group contains at least one non-NULL value. Otherwise, it returns NULL.

What does Concat_ws do in SQL?

The CONCAT_WS() function joins the input strings into a single string. It separates those concatenated strings with the separator specified in the first argument. Note that the CONCAT_WS() requires at least two input strings. It means that if pass zero or one input string argument, the function will raise an error.

What is MySQL coalesce?

The COALESCE() function returns the first non-null value in a list.

How do I merge rows in MySQL?

To merge rows in MySQL, use GROUP_CONCAT().

How do I concatenate two columns in SQL with a hyphen?

Do it with two concats: select concat(concat(amt, ‘-‘), endamt) as amount from mstcatrule; concat(amt,’-‘) concatenates the amt with the dash and the resulting string is concatenated with endamt .

Is NULL and coalesce MySQL?

The COALESCE() function in MySQL is used to return the first non-null value in a specified series of expressions. If this function evaluates all values of the list are null, or it does not find any non-null value, then it returns NULL.