How do I count NULL values in Oracle SQL?
It can be accomplished in Oracle just in 1 row: SELECT COUNT(NVL(potential_null_column, 0)) FROM table; Function NVL checks if first argument is null and treats it as value from second argument.
Does COUNT consider NULL values Oracle?
Using COUNT to count the number of records with values of attributes. The COUNT function counts the number of records that have non-NULL values in a field for each GROUP BY result. Because all of the records have the same value for Size, there is only one group, and thus only one record.
Is the table _ rows null for information _ schema tables?
TABLE_ROWS is NULL for INFORMATION_SCHEMA tables. For InnoDB tables, the row count is only a rough estimate used in SQL optimization. (This is also true if the InnoDB table is partitioned.) The average row length.
How to get Count of non NULL values in SQL?
COUNT (column_name) always gives you the count of NON NULL values. Create a generic function like this which can take schema name and table name as arguments. Here I am constructing select statements joined together by UNION ALL s each returning the value of the column_name and it’s count for all columns when executed dynamically.
How can I get Count of all the columns in a table?
You may need to add quoted identifiers if you’ve got spaces or other special characters in your column names. Then you can copy that output to another query and add the missing parts of the query. I’ve added and is_nullable = ‘YES’ because it’s a waste of time to check NOT NULL columns.
How to get table metadata using information _ schema?
The query selects all of the columns from the INFORMATION_SCHEMA.TABLES view except for is_typed, which is reserved for future use, and ddl, which is hidden from SELECT * queries. The metadata returned is for all tables in mydataset in your default project. mydataset contains the following tables: