MariaDB Check Empty String

In this MariaDB tutorial, we will discuss the MariaDB Check Empty String condition and look at several examples related to it. There are lists of the topic that comes under discussion:

• MariaDB Check Empty String
• MariaDB Check Empty String But Not Null
• MariaDB Check Empty String But Not Empty
• MariaDB Check Empty String Count
• MariaDB Check Empty String Contains Substring
• MariaDB Check Empty String Coalesce
• MariaDB Check Empty String Date
• MariaDB Check Empty String Exists
• MariaDB Check Empty String Enum
• MariaDB Check Empty String Greater Than
• MariaDB Check Empty String Group By
• MariaDB Check Empty String In
• MariaDB Check Empty String JSON
• MariaDB Check Empty String Max
• MariaDB Check Empty String Min
• MariaDB Check Empty String Order By
• MariaDB Check Empty String Partition
• MariaDB Check Empty String Substring
• MariaDB Check Empty String To 0
• MariaDB Check Empty String Update
• MariaDB Check Empty String Year

MariaDB Check Empty String

Here we will understand and learn how to use the MariaDB WHERE condition for checking the empty string of a table in a query. And it will be easy to explain it with the help of syntax and an example.

When executing the SELECT statement in MariaDB, the WHERE condition has been used to sort records in the results. It’s also used with commands like INSERT, DELETE, and UPDATE. The following syntax of the MariaDB WHERE condition for checking empty string by the following query:

SYNTAX:

SELECT expression FROM TABLE_NAME
WHERE COLUMN_NAME=' ';

First, let’s have a look at the MIT_STUDENTS table by the following query:

SELECT * FROM MIT_STUDENTS;

In this preceding query, we have used the SELECT statement to retrieve all records from the MIT_STUDENTS table.

Here is an illustrated example of the MariaDB WHERE condition for checking an empty string by the following query:

EXAMPLE:

SELECT * FROM MIT_STUDENTS
WHERE FIRST_NAME= ' ';

in this above query, we have used the SELECT statement to retrieve all records from the MIT_STUDENTS table with the help of the WHERE condition. In the WHERE condition, we have to select empty string records from the FIRST_NAME column.

If the WHERE condition gets executed, it will retrieve all records from the MIT_STUDENTSble by using the SELECT statement.

Suppose there is no empty string in the FIRST_NAME column then also the query will be executed. And there will be no output column.

In this section, we have understood how to find empty strings from the table by using just the WHERE condition in the query.

Read: MariaDB Check String Length

MariaDB Check Empty String But Not Null

In this section, we will learn and understand how to use the MariaDB WHERE condition for checking empty strings and also use the IS NOT NULL condition in a query. It is explained with the help of an illustrated example.

In MariaDB, the IS NOT NULL condition is used to check records that carried NULL in the column_name or expression from using the SELECT statement.

EXAMPLE:

SELECT * FROM MIT_STUDENTS 
WHERE FIRST_NAME=' ' 
AND PHYSICS IS NOT NULL;

In this query, we have used the SELECT statement to retrieve all records from the MIT_STUDENTS table by using the WHERE condition. In the WHERE condition, the FIRST_NAME column will select records that carry empty strings.

And the PHYSICS column doesn’t carry the NULL value as a number in the MIT_STUDENTS table.

So if the WHERE condition gets TRUE, then it will retrieve all records from the MIT_STUDENTS table by using the SELECT statement.

In this section, we have understood how to use the WHERE condition with the IS NOT NULL condition which helped to find the empty string from the MIT_STUDENTS table.

Read: MariaDB Check If Rows Exists

MariaDB Check Empty String But Not Empty

In this sub-topic, we will learn and understand how to use the MariaDB WHERE condition for checking empty strings with the NOT EQUAL operator in the query. It is explained with the help of an illustrated example.

In MariaDB, the NOT EQUAL operator is used to testify to nonequality in the query.

EXAMPLE:

SELECT * FROM MIT_STUDENTS 
WHERE FIRST_NAME != ' '
LIMIT 10;

• In this query, we have used the MariaDB SELECT statement to retrieve all records from the MIT_STUDENTS table with the WHERE condition.
• In the WHERE condition, we select records from the FIRST_NAME column which doesn’t carry an empty string.
• If the WHERE condition gets TRUE then it will retrieve all records from the MIT_STUDENTS table by the SELECT statement.
• At the end of the query, we have used the LIMIT clause as LIMIT 10 to retrieve all records from the MIT_STUDENTS table by using the SELECT statement.

In this sub-topic, we have understood the use of the NOT EQUAL operator in the WHERE condition for checking the empty string in the MIT_STUDENTS table.

Read: MariaDB Insert Into Select

MariaDB Check Empty String Count

We will learn and understand how to use the MariaDB WHERE condition with the COUNT function to check empty strings in the query. It is explained with the help of an illustrated example.

In MariaDB, the COUNT function is used to count the total number of rows of an expression or column_name in the query. Let’s see an example of the MariaDB COUNT function with the WHERE condition for checking empty strings by the following query:

EXAMPLE:

SELECT COUNT(*) FROM MIT_STUDENTS 
WHERE FIRST_NAME=' ';

In the MariaDB SELECT query, we have used the COUNT function on all the columns of the MIT_STUDENTS table by using the WHERE condition. In the COUNT function, it will count all records from the MIT_STUDENTS table.

In the WHERE condition, the FIRST_NAME column will carry all records whose names carry empty strings in the MIT_STUDENTS table.

If the WHERE condition is satisfied, it will retrieve all records from the MIT_STUDENTS te using the SELECT statement.

We have understood the MariaDB COUNT function with the WHERE condition for checking the empty string in the MIT_STUDENTS table. It may help us to understand how to check empty strings in the MIT_STUDENTS table.

Read: MariaDB GROUP BY with Example

MariaDB Check Empty String Contains Substring

We will learn and understand how to use the MariaDB SUBSTRING function with the BETWEEN condition which will be used to check empty strings in a query. And it is explained with the help of an illustrated example.

In MariaDB, the SUBSTRING function is used to extract a substring from the expression or column_name in the query. Let’s see the syntax of the MariaDB SUBSTRING function with the WHERE condition to check empty strings by the following query:

SYNTAX:

SELECT EXPRESSION,SUBSTRING(EXPRESSION,START_POSTITION, [FOR LENGTH]) FROM TABLE_NAME
WHERE COLUMN_NAME=' ';

The syntax explanation:

• START_POSITION: The position from which it will extract. The first position of the string will always 1.
• LENGTH: It is optional and the number of the characters to be extracted. If the parameters are removed then it will give the whole string.

Here is an illustrated example of the MariaDB SUBSTRING function with the WHERE condition to find an empty string by the following query:

EXAMPLE:

SELECT SUBSTRING(FIRST_NAME,2) FROM MIT_STUDENTS
WHERE FIRST_NAME=' ';

As we see in the above query, we have used the SUBSTRING function on the FIRST_NAME column of the MIT_STUDENTS table based on the WHERE condition. In the SUBSTRING function, it will subtract from 2 in the FIRST_NAME column of the MIT_STUDENTS table.

In the WHERE condition, the FIRST_NAME will select records that carry empty strings in the MIT_STUDENTS table.

If the WHERE condition is satisfied, it will retrieve all records from the MIT_STUDENTS te by using the SELECT statement.

Note that the SUBSTRING function can’t provide substring from the FIRST_NAME column because of the WHERE condition. In the WHERE condition, the FIRST_NAME column was needed to find the empty string from the MIT_STUDENTS table.

This section helps us to understand how to check empty strings in the MIT_STUDENTS table by using the SUBSTRING function with the WHERE condition.

Read: MariaDB Temporary Table

MariaDB Check Empty String Coalesce

In this section, we will understand and learn how to use the MariaDB COALESCE function to check an empty string in the query. And it will be easy to explain it with the help of an illustrated example.

In MariaDB, the COALESCE function is used to return NON-NULL expression from the expressions or column_names in the query. Let’s see the syntax of the MariaDB COALESCE function to find an empty string by the following query:

SYNTAX:

SELECT COALESCE(expression_1,expression_n,expression_n) FROM TABLE_NAME;

The syntax explanation:

• expression_1, expression_2,expression_n: It is used to test NON-NULL values in the expression or column_name of the table.

Here is a sample example of the MariaDB COALESCE function to find an empty string in the table by the following query:

EXAMPLE:

SELECT COALESCE(PHYSICS,'Empty String') AS EMPTY_FIRSTNAME, 
PHYSICS, MATHS
FROM MIT_STUDENTS;

In this query, we have used the COALESCE function on the PHYSICS column from the MIT_STUDETNS table. We have also selected the records of the PHYSICS and MATHS columns from the MIT_STUDENTS table by using the SELECT statement.

In the COALESCE function, it replaced the NULL value with the EMPTY STRING value for every record of the PHYSICS column in the MIT_STUDENTS table.

In this sub-topic, we have used the COALESCE function is used to find empty strings in the query. We hope that the example made it easy to understand the concept of checking the empty strings of the MIT_STUDENTS table.

Read: MariaDB Select Statement

MariaDB Check Empty String Date

Here we will understand and learn how to use the MariaDB DATE function with the WHERE condition for checking empty strings in the table by the query. And it is explained with the help of an illustrated example.

In MariaDB, the DATE function is used to extract a date from the date value or DateTime expression or column_name in the query. Let’s use an example of the MariaDB DATE function with the WHERE condition by the following query:

EXAMPLE:

SELECT DATE(JOINING_DATE),FULL_NAME FROM FAZZRO_COMPANY
WHERE FULL_NAME=' ';

In this preceding query, we have used the DATE function on the JOINING_DATE column in the FAZZRO_COMPANY table. We have also selected all records of the FULL_NAME column by using the SELECT statement.

In the WHERE condition, the FULL_NAME column will catch records that carry empty strings in the FAZZRO_COMPANY table. If the WHERE condition is TRUE, it will retrieve all records from the FAZZRO_COMPANY table using the SELECT statement.

In this tutorial, we have understood how to use the MariaDB DATE function with the WHERE condition to find an empty string in the table. For the explanation part, we have used an example.

Read: MariaDB Date Greater Than – Detailed Guide

MariaDB Check Empty String Exists

In this section, we will learn and understand how to use the MariaDB EXISTS condition on a subquery. We also use the WHERE condition in a subquery and which is explained with the help of an illustrated example.

When the MariaDB EXISTS condition is used with a subquery, it is said to be “met” if the inner select statement returns at least one record. Under a SELECT, INSERT, UPDATE, or DELETE statement, it can be utilized. Let’s an example of the MariaDB EXISTS statement with the WHERE condition by the following query:

EXAMPLE:

SELECT FULL_NAME FROM FAZZRO_COMPANY
WHERE EXISTS
(SELECT * FROM FAZZRO_COMPANY
WHERE FULL_NAME= '  ');

In the OUTER SELECT statement, we select all records of the FULL_NAME column from the FAZZRO_COMPANY table by using the WHERE condition. Whereas in the EXISTS statement, we select all records from the FAZZRO_COMPANY table based on the WHERE condition.

In the WHERE condition, the FULL_NAME column will select an empty string from the FAZZRO_COMPANY table. If the WHERE condition gets TRUE, it will retrieve all records from the FAZZRO_COMPANY table using the SELECT statement.

If the WHERE EXISTS statement condition gets TRUE then it will retrieve all records from the FAZZRO_COMPANY table.

In this section, we hope that you have understood how to use the MariaDB EXISTS statement with the WHERE condition for checking empty strings in a query. We have used a sample example to explain it properly.

Read: MariaDB on Duplicate Key Update

MariaDB Check Empty String Greater Than

In this sub-topic, we will understand and learn how to use the MariaDB WHERE condition with the GREATER THAN operator in the query. And it is explained with the help of an illustrated example.

In MariaDB, the GREATER THAN operator is used after the WHERE condition which will retrieve records after selecting from the SELECT statement. It is also used in the UPDATE, DELETE and INSERT statements. The main use of the GREATER THAN operator is used to find greater value from numbers in the WHERE condition.

Here is an example of the MariaDB WHERE condition with the GREATER THAN operator to find an empty string in a table by the following query:

EXAMPLE:

SELECT * FROM fazzro_company 
WHERE FULL_NAME= '  '  
AND ID>10;

In this query, we have used the SELECT statement to retrieve all records from the FAZZRO_COMPANY table by using the WHERE condition. In the WHERE condition, the FULL_NAME column will select an empty string from the FAZZRO_COMPANY table.

And in the ID column, it will select values greater than 10 from the FAZZRO_COMPANY table. If the WHERE condition gets fulfilled, it will retrieve all records from the FAZZRO_COMPANY te by using the SELECT statement.

In this tutorial, we have understood how to use the MariaDB WHERE condition with the GREATER THAN operator to find an empty string in a table. For better understanding, we have used an example.

Read: MariaDB DateTime Tutorial

MariaDB Check Empty String Group By

In this section, we will understand and learn how to use the MariaDB BETWEEN condition with the GROUP BY clause for checking empty strings in the table from the query. It is explained with the help of an illustrated example.

The group by clause in MariaDB divides a result’s rows into categories. The aggregate functions count(), min(), max(), sum(), and avg() are frequently used with the group by function to obtain attributes of groups. For example, the number of elements (count), the total of values (sum), the maximum element (max), the minimum element (min), and the average of elements (avg).

Here is a sample example of the MariaDB BETWEEN condition with the GROUP BY clause in a query by the following example:

EXAMPLE:

SELECT FULL_NAME,JOINING_DATE FROM FAZZRO_COMPANY
WHERE FULL_NAME= ' ' 
GROUP BY JOINING_DATE;

In this preceding query, we have used the SELECT statement to select records of the FULL_NAME and JOINING_DATE columns from the FAZZRO_COMPANY table based on the WHERE condition. In the WHERE condition, the FULL_NAME column will select an empty string from the FAZZRO_COMPANY table.

And grouped them by the JOINING_DATE column by using the GROUP BY clause. If the WHERE condition gets executed, it will retrieve all records from the FAZZRO_COMPANY te by using the SELECT statement.

In this section, we have used the MariaDB BETWEEN condition with the GROUP BY clause which was used to check empty strings in a table by the query. And it is easy to explain with the help of an illustrated example.

Read: MariaDB Select Where Not Empty

MariaDB Check Empty String In

In this section, we will learn and understand how to use the MariaDB WHERE condition with the IN condition for checking empty strings in the table. And it is explained with the help of an illustrated example.

In a SELECT, INSERT, UPDATE, or DELETE query, the MariaDB IN condition is being used to help avoid the requirement for several OR conditions. Let’s see an example of the MariaDB BETWEEN condition with the IN condition for checking an empty string in a table by the following query:

EXAMPLE:

SELECT FULL_NAME,JOINING_DATE 
FROM FAZZRO_COMPANY 
WHERE FULL_NAME IN(' ' ,' ');

As we see in the above query, we have used the SELECT statement to select the FULL_NAME and JOINING_DATE columns from the FAZZRO_COMPANY table used with the WHERE condition.

In the WHERE condition, the FULL_NAME column will return all records from the FAZZRO_COMPANY table which carries an empty string in that column of the table. If the WHERE condition gets TRUE, it will retrieve all records from the FAZZRO_COMPANY le using the SELECT statement.

In this section, we have understood to check an empty string in the table by using the WHERE condition with the IN condition in the query.

Read: MariaDB Not Between

MariaDB Check Empty String JSON

We will learn and understand how to use the MariaDB BETWEEN conditions on the JSON value in the query. It is explained with the help of an illustrated example.

MariaDB’s JSON data type is a replacement for LONGTEXT, which was designed to work with MySQL’s JSON data type. Because it violates the SQL standard, MariaDB supports the JSON data format as a LONGTEXT instead, and MariaDB’s benchmarks show that efficiency is at least comparable.

Here is a sample example of the MariaDB WHERE condition with the JSON data type by the following query:

EXAMPLE:

SELECT * FROM json_demo
WHERE USER_NAME='';

In this preceding query, we used the SELECT statement to retrieve all records from the JSON_DEMO table and used the WHERE condition. In the WHERE condition, we have used the USER_NAME column with the equal operator to find an empty string in the JSON data type.

If the WHERE condition gets TRUE, it will retrieve all records from the JSON_DEMO le by using the SELECT statement.

In this section, we hope that you have understood how to use the WHERE condition on the JSON data type to find an empty string in the JSON_DEMO table from the query.

Read: MariaDB Insert Multiple Rows

MariaDB Check Empty String Max

In this section, we will understand and learn how to use the MariaDB MAX function with the BETWEEN condition to find an empty string in the query. It is explained with the help of an illustrated example.

In MariaDB, the MAX function is used to find the max value from the expression or column_name in the query. Let’s see an example of the MariaDB MAX function with the BETWEEN condition to find an empty string by the following query:

EXAMPLE:

SELECT *,MAX(ID) FROM FAZZRO_COMPANY
WHERE FULL_NAME='  ';

In this query, we have used the SELECT statement to retrieve all records from FAZZRO_COMPANY. And we have also used the MAX function on the ID column to find the highest value of id in the FAZZRO_COMPANY table.

In the WHERE condition, the FULL_NAME column is used with the EQUAL operator to find an empty string in the FAZZRO_COMPANY table. If the WHERE condition gets executed, it will retrieve all records from the FAZZRO_COMPANY te by using the SELECT statement.

In this sub-topic, we have understood how to use the MariaDB MAX function with the BETWEEN condition to find the empty string in the FAZZRO_COMPANY table by the query.

Read: MariaDB Greatest Function

MariaDB Check Empty String Min

In this section, we will understand and learn how to use the MariaDB MIN function with the BETWEEN condition to find an empty string in the query. It is explained with the help of an illustrated example.

In MariaDB, the MIN function is used to find the min value from the expression or column_name in the query. Let’s see an example of the MariaDB MIN function with the BETWEEN condition to find an empty string by the following query:

EXAMPLE:

SELECT *, MIN(ID) FROM FAZZRO_COMPANY
WHERE FULL_NAME='  ';

In this query, we have used the SELECT statement to retrieve all records from FAZZRO_COMPANY. And we have also used the MIN function on the ID column to find the lowest value of id in the FAZZRO_COMPANY table.

In the WHERE condition, the FULL_NAME column is used with the EQUAL operator to find an empty string in the FAZZRO_COMPANY table. If the WHERE condition gets TRUE,t, it will retrieve all records from the FAZZRO_COMPANY table using the SELECT statement.