If you’re getting an error that reads “could not determine polymorphic type because input has type unknown” when using the array_shuffle() function in PostgreSQL, it’s probably because your argument is of the wrong type.

The array_shuffle() function requires an array as its argument. Passing a non-array value will result in an error. The actual error can vary, depending on the argument you pass, but either way, the error is usually due to a non-array argument being passed.

To fix this error, be sure to pass an array as the argument when calling the array_shuffle() function.

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If you’re getting an error that reads “multidimensional arrays must have array expressions with matching dimensions” it’s probably because you’re trying to create a multi-dimensional array where the inner arrays at the same level have different dimensions.

Multidimensional arrays must be rectangular. To fix this issue, make sure all arrays at the same level have the same dimensions.

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If you’re getting a PostgreSQL error that reads something like “cannot subscript type text because it does not support subscripting” when selecting data from a database, it’s probably because you’re trying to perform some sort of array operation against a non array value.

The above error specifically mentions text data but we could get the same error when using a different data type, like an integer, character varying, etc.

To fix this issue, be sure to run the array operations against actual arrays. If working with non array data, then don’t use array operations against that data.

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If you’re getting a PostgreSQL error that reads something like “function generate_subscripts(text[], integer, integer) does not exist“, it’s probably because your third argument is of the wrong type when using the generate_subscripts() function.

The above error specifically implies that an integer was passed as the third argument, but it must be a boolean value.

The third argument of the generate_subscripts() function is optional, but if passed, it must be a boolean expression.

To fix this error, either pass a boolean value as the third argument, or eliminate the third argument altogether.

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If you’re getting an error that reads “could not determine polymorphic type because input has type unknown” when using the generate_subscripts() function in PostgreSQL, it’s probably because your first argument is of the wrong type.

The generate_subscripts() function requires an array as its first argument. Passing a non-array value will result in an error. The actual error can vary, depending on the argument you pass, but regardless, the error is usually due to a non-array argument being passed.

To fix this error, be sure to pass an array as the argument when calling generate_subscripts().

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If you’re getting an error that starts with “sample size must be between…” when using the array_sample() function in PostgreSQL, it’s probably because your second argument is either a negative value, or it’s larger than the number of elements in the array.

The second argument must be no less than zero, and it can’t be any larger than the number of elements in the array.

To fix this error, be sure that your second argument is greater than zero and less than or equal to the number of elements in the array at the first argument.

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If you’re getting a PostgreSQL error that reads “function generate_subscripts(integer, integer) does not exist“, it’s probably because your first argument is not an array. This specific error message implies that the first argument is an integer, but we’d get a similar error when passing a numeric argument.

The first argument for this function must be an array.

To fix this error, be sure that your first argument to generate_subscripts() is an array.

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If you’re getting an error that reads “invalid input syntax for type integer…” when using the array_sample() function in PostgreSQL, it’s probably because your second argument is not an integer.

The second argument for this function must be an integer.

To fix this error, be sure that your second argument to array_sample() is an integer.

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If you’re getting an error that reads “could not determine polymorphic type because input has type unknown” when using the array_sample() function in PostgreSQL, it’s probably because your first argument is of the wrong type.

The array_sample() function requires an array as its first argument. Passing a non-array value will result in an error. The actual error can vary, depending on the argument you pass, but either way, the error is usually due to a non-array being passed.

To fix this error, be sure to pass an array as the first argument when calling the array_sample() function.

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If you’re getting an error that reads “function array_sample(integer, integer) does not exist” when using the array_sample() function in PostgreSQL, it’s probably because your first argument is not an array. In particular, this specific error message implies that the first argument is an integer.

The first argument for this function must be an array.

To fix this error, be sure that your first argument to array_sample() is an array, not an integer.

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