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1. #Android sqlite insert if not exists else update how to#
2. #Android sqlite insert if not exists else update update#
3. #Android sqlite insert if not exists else update code#

SYNTAX: INSERT INTO TABLE_NAME(COLUMN_1,COLUMN_2,COLUMN_N)

But if the subquery in the NOT EXISTS clause is TRUE then it will not return any row at all. The MariaDB INSERT INTO EXISTS explains that if a subquery returns any rows at all then the NOT EXISTS subquery is FALSE. And it will be explained with the help of an illustrated example.

#Android sqlite insert if not exists else update how to#

Over here we will understand how to insert into if no exists in the MariaDB query. Read: MariaDB Median MariaDB Insert Into If Not Exists

#Android sqlite insert if not exists else update update#

Here is an illustrated example of the ON DUPLICATE KEY UPDATE clause which will be used at the end of a query for the INSERT clause as shown below:įirst, it will execute the regular insert query above in the MariaDB but when duplicate values are found then MariaDB will perform an update instead of insertion by using the ON DUPLICATE KEY UPDATE clause. The MariaDB ON DUPLICATE KEY UPDATE clause is used to update the rows with new values when a duplicate value is found in the UNIQUE KEY or PRIMARY KEY constraint. In this section, we will understand how to insert it if not exists, for that we will use the ON DUPLICATE KEY UPDATE clause in MariaDB and which is explained with the help of an illustrated example. Read: MariaDB Between MariaDB Insert If Not Exists Else Update And it will produce a warning of the PRIMARY KEY constraint for duplicate key values. In this query, with the help of the INSERT IGNORE statement, MariaDB will insert a row if the values do not exist in the table. Here is an example of the INSERT IGNORE statement to insert a row if not exist in the query with the help of the following query:ĮXAMPLE: INSERT IGNORE INTO STATES_OF_USA(STATE_ID,STATE_NAME,STATE_SHORTFORM,STATE_POPULATION) MariaDB SELECT statement for STATES_OF_USA The MariaDB SELECT statement retrieves all records from the STATES_OF_USA table. The MariaDB INSERT IGNORE command is typically used to turn an error that MySQL throws when you use a regular INSERT statement into a warning, allowing your query to continue running undisturbed.įirst, let’s have a look at the STATES_OF_USA table by the following query: SELECT * FROM STATES_OF_USA There are three ways we can use to “insert if not exist” in MySQL: If we want to do still insertion in the table when the data does not exist then we need to create a work-around solution with the statements provided by MySQL. It is because when we have a column of the PRIMARY KEY or UNIQUE KEY constraint then it will throw an error each time when we will insert a new row with duplicate values for these columns.

Here we will understand how to insert rows in the table if it does not exists in MariaDB. MariaDB Add Unique Constraints If Not Exists.

#Android sqlite insert if not exists else update code#

Heres some example code where we have sql scripts in an array. The idea is to execute the sql if it exceptions on an alter table call we can find the alter table line in the sql and return the remaining lines and execute until it either succeeds or no more matching alter table lines can be found. Luckily the error message gives us all the information we need to do this. So the idea of catching an exception is acceptable and then moving on. Typically you are not going to run this in realtime or often. However, the original question was to input a sql script that would be executed by a single db execute and all the solutions ( like checking to see if the column is there ahead of time ) would require the executing program either have knowledge of what tables and columns are being altered/added or do pre-processing and parsing of the input script to determine this information. All these answers are fine if you execute one line at a time.