Error while executing the query postgresql

PostgreSQL Error code 23505 – How to fix

Wondering how to fix PostgreSQL Error code 23505? We can help you.

One of the most common error codes with the PostgreSQL database is 23505. It can be seen along with the error message “duplicate key violates unique constraint”

Here at Bobcares, we often handle requests from our customers to fix similar PostgreSQL errors as a part of our Server Management Services. Today we will see how our support engineers fix this for our customers.

How PostgreSQL Error code 23505

At times we may get the following message when trying to insert data into a PostgreSQL database:

This happens when the primary key sequence in the table we’re working on becomes out of sync. And this might likely be because of a mass import process.

Here we have to manually reset the primary key index after restoring it from a dump file.

To check whether the values are out of sync, we can run the following commands:

If the first value is higher than the second value, our sequence is out of sync.

We can back up our PG database and then run the following command:

This will set the sequence to the next available value that’s higher than any existing primary key in the sequence.

To Resolve this error in VMware

When vpxd process crashes randomly after upgrading to vCenter Server 6.5 with the following error:

In the vpxd.log file, we can see entries similar to the one given below:

–> Error while executing the query” is returned when executing SQL statement “INSERT INTO VPX_GUEST_DISK (VM_ID, PATH, CAPACITY, >FREE_SPACE) VALUES (?, ?, ?, ?)”
And in the postgresql.log file, you see entries similar to the one given below:

Steps to fix the error are given below:

vCenter Services can be given a service restart. If the starting fails to initialize the service and shows the same crash reason, we can fix this by removing the impacted guest disk entry from vCenter Server Database. This information is safe to remove as it will be re-populated from the host.

For vCenter Server with vPostgres database:

1. First, take a snapshot of the vCenter Server machine before proceeding.

2. Then connect the vCenter Database.

3. And identify the guest disk entry using the following query:

4. For deleting the duplicate value we can use the following command:

We can get the VM id from the vpxd.log error entry

5. Finally start the Service.

We can delete the snapshot after observing the stability of the vCenter Server.

[Need assistance? We can help you]

Conclusion

In short, we saw how our Support Techs fix PostgreSQL Error code 23505 for our customers.

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Источник

Error while executing install/upgrade — Install.v11.sql #111

Thank for creating and maintaining this package!

I’m getting this exception from PostgreSQL when starting my application Npgsql.PostgresException (0x80004005): 42601: syntax error at or near «AS» .

Looking at the hangfire.schema table the version column is 10 and Install.v10.sql doesn’t contain any AS keyword, so it must be failing on Install.v11.sql . The app still boots and everything seems to be working as normal (which makes sense since v11 only changes the column type).

I’m using PostgreSQL 9.5.

Let me know if I can provide any more information.

The text was updated successfully, but these errors were encountered:

The problem here is that ALTER SEQUENCE . AS syntax was only introduced in Postgres 10+.

Officially supported Postgres versions are 11 , 10 , 9.6 , 9.5 , 9.4 . A lot of people are still using 9.X . For example Google Cloud SQL is using 9.6 .

So I’ve dug into Postgres 9.4 documentation and found this:

Sequences are based on bigint arithmetic, so the range cannot exceed the range of an eight-byte integer (-9223372036854775808 to 9223372036854775807).

This means that to convert IDs to BIGINT you don’t need to alter sequences at all since they’re already based on bigint . So all you need to do is change the ID type.

If min required version is going to be 10 I suggest to change to IDENTITY columns instead.

I do suggest that 9.4+ is supported until official EOL in November 11, 2021. Especially considering .NET demographics.

I don’t think you are right (or the documentation is right). In PostgreSQL 9 the underlying datatype of an serial was integer and created the sequence automatically.

What would be a better way is to not execute the ALTER SEQUENCE AS BIGINT; when the PostgreSQL version does not allow it. What do you think?

You’re right — the data type of the column is int for serial by default. But not the sequence, you can check locally by issuing SELECT * FROM [name of sequence] and you’ll see that max value is the same as max value of bigint. It’s decoupled from the data type of the ID column.

What Is The Range Of Values Generated By A Sequence?
Sequences generate 64-bit signed integers. The serial pseudotype that we used above is a 32-bit signed integer: if you want to use the full 64-bit range of the underlying sequence, use the serial8 pseudotype instead.

It’s saying the same thing. When you use serial to magically create the id and sequence, the id is created as int , but the underlying sequence is bigint .

EDIT: It’s not that hard to check. We can do up to v10 migration, then set the sequence current value to max(int)-1 , alter the type of id to bigint and then insert 2-3 rows.

All the mess is because historically SQL servers each had their own magical ways of setting up sequences and identity columns and only recently they’re moving towards the standard.

EDIT 2:
In case I haven’t convinced you then there are some hacky ways to execute SQL based on PostgreSQL version. But it seems like it would be less hacky, to have 2 v11 migrations and check the version in C# code. Or use some template pre-processing. It still feels very dirty.

Источник

Почему не восстанавливаются резервные копии?

Доброго дня.
Появилась проблема, и я очень прошу помощи.

Суть.
Есть сервер с CentOS 6, на базе которого крутится postgres.

Там имеются базы данных, которые используются как базы 1С.
На этом сервере есть sh скрипт который выполняется по cron. Суть этого скрипта, это бэкапить базы на NAS. Пример скрипта, приведу ниже.

И вроде всё делается нормально, бэкапы делаются, я спокоен, и пару мепсяцев один из них разворачивал, и тут попытался сделать это снова с помощью.

База изначально была создана с помощью консоли 1С.

И вот, после восстановления бэкапа я получаю следующее.

Другие бэкапы так же пытался восстановить. Количество ерроров меняется, но суть остаётся неизменной.
Я получаю следующее.

И вот полный текст.
Невосстановимая ошибка
Ошибка при выполнении запроса POST к ресурсу /e1cib/login:
по причине:
Ошибка при выполнении операции с информационной базой
Ошибка СУБД:
XX000: ERROR: There are 2 candidates for ‘mchar_pattern_fixed_prefix’ function’

по причине:
Ошибка СУБД:
XX000: ERROR: There are 2 candidates for ‘mchar_pattern_fixed_prefix’ function’

Что то мне подсказывает что это может быть типичная ошибка новичка, но я пока ума не приложу, в какую сторону копать?

PS. Я понимаю что и CentOS старый, и PGSQL. Но пока не было возможности остановить предприятие более чем на 8 часов, что бы всё перенести, а текучку никто не отменял:(

Источник

Error while executing install/upgrade — Install.v11.sql #111

Thank for creating and maintaining this package!

I’m getting this exception from PostgreSQL when starting my application Npgsql.PostgresException (0x80004005): 42601: syntax error at or near «AS» .

Looking at the hangfire.schema table the version column is 10 and Install.v10.sql doesn’t contain any AS keyword, so it must be failing on Install.v11.sql . The app still boots and everything seems to be working as normal (which makes sense since v11 only changes the column type).

I’m using PostgreSQL 9.5.

Let me know if I can provide any more information.

The text was updated successfully, but these errors were encountered:

The problem here is that ALTER SEQUENCE . AS syntax was only introduced in Postgres 10+.

Officially supported Postgres versions are 11 , 10 , 9.6 , 9.5 , 9.4 . A lot of people are still using 9.X . For example Google Cloud SQL is using 9.6 .

So I’ve dug into Postgres 9.4 documentation and found this:

Sequences are based on bigint arithmetic, so the range cannot exceed the range of an eight-byte integer (-9223372036854775808 to 9223372036854775807).

This means that to convert IDs to BIGINT you don’t need to alter sequences at all since they’re already based on bigint . So all you need to do is change the ID type.

If min required version is going to be 10 I suggest to change to IDENTITY columns instead.

I do suggest that 9.4+ is supported until official EOL in November 11, 2021. Especially considering .NET demographics.

I don’t think you are right (or the documentation is right). In PostgreSQL 9 the underlying datatype of an serial was integer and created the sequence automatically.

What would be a better way is to not execute the ALTER SEQUENCE AS BIGINT; when the PostgreSQL version does not allow it. What do you think?

You’re right — the data type of the column is int for serial by default. But not the sequence, you can check locally by issuing SELECT * FROM [name of sequence] and you’ll see that max value is the same as max value of bigint. It’s decoupled from the data type of the ID column.

What Is The Range Of Values Generated By A Sequence?
Sequences generate 64-bit signed integers. The serial pseudotype that we used above is a 32-bit signed integer: if you want to use the full 64-bit range of the underlying sequence, use the serial8 pseudotype instead.

It’s saying the same thing. When you use serial to magically create the id and sequence, the id is created as int , but the underlying sequence is bigint .

EDIT: It’s not that hard to check. We can do up to v10 migration, then set the sequence current value to max(int)-1 , alter the type of id to bigint and then insert 2-3 rows.

All the mess is because historically SQL servers each had their own magical ways of setting up sequences and identity columns and only recently they’re moving towards the standard.

EDIT 2:
In case I haven’t convinced you then there are some hacky ways to execute SQL based on PostgreSQL version. But it seems like it would be less hacky, to have 2 v11 migrations and check the version in C# code. Or use some template pre-processing. It still feels very dirty.

Источник

Error while executing the query postgresql

Control structures are probably the most useful (and important) part of PL/pgSQL . With PL/pgSQL ‘s control structures, you can manipulate PostgreSQL data in a very flexible and powerful way.

43.6.1. Returning from a Function

There are two commands available that allow you to return data from a function: RETURN and RETURN NEXT .

43.6.1.1. RETURN

RETURN with an expression terminates the function and returns the value of expression to the caller. This form is used for PL/pgSQL functions that do not return a set.

In a function that returns a scalar type, the expression’s result will automatically be cast into the function’s return type as described for assignments. But to return a composite (row) value, you must write an expression delivering exactly the requested column set. This may require use of explicit casting.

If you declared the function with output parameters, write just RETURN with no expression. The current values of the output parameter variables will be returned.

If you declared the function to return void , a RETURN statement can be used to exit the function early; but do not write an expression following RETURN .

The return value of a function cannot be left undefined. If control reaches the end of the top-level block of the function without hitting a RETURN statement, a run-time error will occur. This restriction does not apply to functions with output parameters and functions returning void , however. In those cases a RETURN statement is automatically executed if the top-level block finishes.

43.6.1.2. RETURN NEXT and RETURN QUERY

When a PL/pgSQL function is declared to return SETOF sometype , the procedure to follow is slightly different. In that case, the individual items to return are specified by a sequence of RETURN NEXT or RETURN QUERY commands, and then a final RETURN command with no argument is used to indicate that the function has finished executing. RETURN NEXT can be used with both scalar and composite data types; with a composite result type, an entire “ table ” of results will be returned. RETURN QUERY appends the results of executing a query to the function’s result set. RETURN NEXT and RETURN QUERY can be freely intermixed in a single set-returning function, in which case their results will be concatenated.

RETURN NEXT and RETURN QUERY do not actually return from the function — they simply append zero or more rows to the function’s result set. Execution then continues with the next statement in the PL/pgSQL function. As successive RETURN NEXT or RETURN QUERY commands are executed, the result set is built up. A final RETURN , which should have no argument, causes control to exit the function (or you can just let control reach the end of the function).

RETURN QUERY has a variant RETURN QUERY EXECUTE , which specifies the query to be executed dynamically. Parameter expressions can be inserted into the computed query string via USING , in just the same way as in the EXECUTE command.

If you declared the function with output parameters, write just RETURN NEXT with no expression. On each execution, the current values of the output parameter variable(s) will be saved for eventual return as a row of the result. Note that you must declare the function as returning SETOF record when there are multiple output parameters, or SETOF sometype when there is just one output parameter of type sometype , in order to create a set-returning function with output parameters.

Here is an example of a function using RETURN NEXT :

Here is an example of a function using RETURN QUERY :

The current implementation of RETURN NEXT and RETURN QUERY stores the entire result set before returning from the function, as discussed above. That means that if a PL/pgSQL function produces a very large result set, performance might be poor: data will be written to disk to avoid memory exhaustion, but the function itself will not return until the entire result set has been generated. A future version of PL/pgSQL might allow users to define set-returning functions that do not have this limitation. Currently, the point at which data begins being written to disk is controlled by the work_mem configuration variable. Administrators who have sufficient memory to store larger result sets in memory should consider increasing this parameter.

43.6.2. Returning from a Procedure

A procedure does not have a return value. A procedure can therefore end without a RETURN statement. If you wish to use a RETURN statement to exit the code early, write just RETURN with no expression.

If the procedure has output parameters, the final values of the output parameter variables will be returned to the caller.

43.6.3. Calling a Procedure

A PL/pgSQL function, procedure, or DO block can call a procedure using CALL . Output parameters are handled differently from the way that CALL works in plain SQL. Each OUT or INOUT parameter of the procedure must correspond to a variable in the CALL statement, and whatever the procedure returns is assigned back to that variable after it returns. For example:

The variable corresponding to an output parameter can be a simple variable or a field of a composite-type variable. Currently, it cannot be an element of an array.

43.6.4. Conditionals

IF and CASE statements let you execute alternative commands based on certain conditions. PL/pgSQL has three forms of IF :

IF . THEN . END IF

IF . THEN . ELSE . END IF

IF . THEN . ELSIF . THEN . ELSE . END IF

and two forms of CASE :

CASE . WHEN . THEN . ELSE . END CASE

CASE WHEN . THEN . ELSE . END CASE

43.6.4.1. IF-THEN

IF-THEN statements are the simplest form of IF . The statements between THEN and END IF will be executed if the condition is true. Otherwise, they are skipped.

43.6.4.2. IF-THEN-ELSE

IF-THEN-ELSE statements add to IF-THEN by letting you specify an alternative set of statements that should be executed if the condition is not true. (Note this includes the case where the condition evaluates to NULL.)

43.6.4.3. IF-THEN-ELSIF

Sometimes there are more than just two alternatives. IF-THEN-ELSIF provides a convenient method of checking several alternatives in turn. The IF conditions are tested successively until the first one that is true is found. Then the associated statement(s) are executed, after which control passes to the next statement after END IF . (Any subsequent IF conditions are not tested.) If none of the IF conditions is true, then the ELSE block (if any) is executed.

Here is an example:

The key word ELSIF can also be spelled ELSEIF .

An alternative way of accomplishing the same task is to nest IF-THEN-ELSE statements, as in the following example:

However, this method requires writing a matching END IF for each IF , so it is much more cumbersome than using ELSIF when there are many alternatives.

43.6.4.4. Simple CASE

The simple form of CASE provides conditional execution based on equality of operands. The search-expression is evaluated (once) and successively compared to each expression in the WHEN clauses. If a match is found, then the corresponding statements are executed, and then control passes to the next statement after END CASE . (Subsequent WHEN expressions are not evaluated.) If no match is found, the ELSE statements are executed; but if ELSE is not present, then a CASE_NOT_FOUND exception is raised.

Here is a simple example:

43.6.4.5. Searched CASE

The searched form of CASE provides conditional execution based on truth of Boolean expressions. Each WHEN clause’s boolean-expression is evaluated in turn, until one is found that yields true . Then the corresponding statements are executed, and then control passes to the next statement after END CASE . (Subsequent WHEN expressions are not evaluated.) If no true result is found, the ELSE statements are executed; but if ELSE is not present, then a CASE_NOT_FOUND exception is raised.

Here is an example:

This form of CASE is entirely equivalent to IF-THEN-ELSIF , except for the rule that reaching an omitted ELSE clause results in an error rather than doing nothing.

43.6.5. Simple Loops

With the LOOP , EXIT , CONTINUE , WHILE , FOR , and FOREACH statements, you can arrange for your PL/pgSQL function to repeat a series of commands.

43.6.5.1. LOOP

LOOP defines an unconditional loop that is repeated indefinitely until terminated by an EXIT or RETURN statement. The optional label can be used by EXIT and CONTINUE statements within nested loops to specify which loop those statements refer to.

43.6.5.2. EXIT

If no label is given, the innermost loop is terminated and the statement following END LOOP is executed next. If label is given, it must be the label of the current or some outer level of nested loop or block. Then the named loop or block is terminated and control continues with the statement after the loop’s/block’s corresponding END .

If WHEN is specified, the loop exit occurs only if boolean-expression is true. Otherwise, control passes to the statement after EXIT .

EXIT can be used with all types of loops; it is not limited to use with unconditional loops.

When used with a BEGIN block, EXIT passes control to the next statement after the end of the block. Note that a label must be used for this purpose; an unlabeled EXIT is never considered to match a BEGIN block. (This is a change from pre-8.4 releases of PostgreSQL , which would allow an unlabeled EXIT to match a BEGIN block.)

43.6.5.3. CONTINUE

If no label is given, the next iteration of the innermost loop is begun. That is, all statements remaining in the loop body are skipped, and control returns to the loop control expression (if any) to determine whether another loop iteration is needed. If label is present, it specifies the label of the loop whose execution will be continued.

If WHEN is specified, the next iteration of the loop is begun only if boolean-expression is true. Otherwise, control passes to the statement after CONTINUE .

CONTINUE can be used with all types of loops; it is not limited to use with unconditional loops.

43.6.5.4. WHILE

The WHILE statement repeats a sequence of statements so long as the boolean-expression evaluates to true. The expression is checked just before each entry to the loop body.

43.6.5.5. FOR (Integer Variant)

This form of FOR creates a loop that iterates over a range of integer values. The variable name is automatically defined as type integer and exists only inside the loop (any existing definition of the variable name is ignored within the loop). The two expressions giving the lower and upper bound of the range are evaluated once when entering the loop. If the BY clause isn’t specified the iteration step is 1, otherwise it’s the value specified in the BY clause, which again is evaluated once on loop entry. If REVERSE is specified then the step value is subtracted, rather than added, after each iteration.

Some examples of integer FOR loops:

If the lower bound is greater than the upper bound (or less than, in the REVERSE case), the loop body is not executed at all. No error is raised.

If a label is attached to the FOR loop then the integer loop variable can be referenced with a qualified name, using that label .

43.6.6. Looping through Query Results

Using a different type of FOR loop, you can iterate through the results of a query and manipulate that data accordingly. The syntax is:

The target is a record variable, row variable, or comma-separated list of scalar variables. The target is successively assigned each row resulting from the query and the loop body is executed for each row. Here is an example:

If the loop is terminated by an EXIT statement, the last assigned row value is still accessible after the loop.

The query used in this type of FOR statement can be any SQL command that returns rows to the caller: SELECT is the most common case, but you can also use INSERT , UPDATE , or DELETE with a RETURNING clause. Some utility commands such as EXPLAIN will work too.

PL/pgSQL variables are replaced by query parameters, and the query plan is cached for possible re-use, as discussed in detail in Section 43.11.1 and Section 43.11.2.

The FOR-IN-EXECUTE statement is another way to iterate over rows:

This is like the previous form, except that the source query is specified as a string expression, which is evaluated and replanned on each entry to the FOR loop. This allows the programmer to choose the speed of a preplanned query or the flexibility of a dynamic query, just as with a plain EXECUTE statement. As with EXECUTE , parameter values can be inserted into the dynamic command via USING .

Another way to specify the query whose results should be iterated through is to declare it as a cursor. This is described in Section 43.7.4.

43.6.7. Looping through Arrays

The FOREACH loop is much like a FOR loop, but instead of iterating through the rows returned by an SQL query, it iterates through the elements of an array value. (In general, FOREACH is meant for looping through components of a composite-valued expression; variants for looping through composites besides arrays may be added in future.) The FOREACH statement to loop over an array is:

Without SLICE , or if SLICE 0 is specified, the loop iterates through individual elements of the array produced by evaluating the expression . The target variable is assigned each element value in sequence, and the loop body is executed for each element. Here is an example of looping through the elements of an integer array:

The elements are visited in storage order, regardless of the number of array dimensions. Although the target is usually just a single variable, it can be a list of variables when looping through an array of composite values (records). In that case, for each array element, the variables are assigned from successive columns of the composite value.

With a positive SLICE value, FOREACH iterates through slices of the array rather than single elements. The SLICE value must be an integer constant not larger than the number of dimensions of the array. The target variable must be an array, and it receives successive slices of the array value, where each slice is of the number of dimensions specified by SLICE . Here is an example of iterating through one-dimensional slices:

43.6.8. Trapping Errors

By default, any error occurring in a PL/pgSQL function aborts execution of the function and the surrounding transaction. You can trap errors and recover from them by using a BEGIN block with an EXCEPTION clause. The syntax is an extension of the normal syntax for a BEGIN block:

If no error occurs, this form of block simply executes all the statements , and then control passes to the next statement after END . But if an error occurs within the statements , further processing of the statements is abandoned, and control passes to the EXCEPTION list. The list is searched for the first condition matching the error that occurred. If a match is found, the corresponding handler_statements are executed, and then control passes to the next statement after END . If no match is found, the error propagates out as though the EXCEPTION clause were not there at all: the error can be caught by an enclosing block with EXCEPTION , or if there is none it aborts processing of the function.

The condition names can be any of those shown in Appendix A. A category name matches any error within its category. The special condition name OTHERS matches every error type except QUERY_CANCELED and ASSERT_FAILURE . (It is possible, but often unwise, to trap those two error types by name.) Condition names are not case-sensitive. Also, an error condition can be specified by SQLSTATE code; for example these are equivalent:

If a new error occurs within the selected handler_statements , it cannot be caught by this EXCEPTION clause, but is propagated out. A surrounding EXCEPTION clause could catch it.

When an error is caught by an EXCEPTION clause, the local variables of the PL/pgSQL function remain as they were when the error occurred, but all changes to persistent database state within the block are rolled back. As an example, consider this fragment:

When control reaches the assignment to y , it will fail with a division_by_zero error. This will be caught by the EXCEPTION clause. The value returned in the RETURN statement will be the incremented value of x , but the effects of the UPDATE command will have been rolled back. The INSERT command preceding the block is not rolled back, however, so the end result is that the database contains Tom Jones not Joe Jones .

A block containing an EXCEPTION clause is significantly more expensive to enter and exit than a block without one. Therefore, don’t use EXCEPTION without need.

Example 43.2. Exceptions with UPDATE / INSERT

This example uses exception handling to perform either UPDATE or INSERT , as appropriate. It is recommended that applications use INSERT with ON CONFLICT DO UPDATE rather than actually using this pattern. This example serves primarily to illustrate use of PL/pgSQL control flow structures:

This coding assumes the unique_violation error is caused by the INSERT , and not by, say, an INSERT in a trigger function on the table. It might also misbehave if there is more than one unique index on the table, since it will retry the operation regardless of which index caused the error. More safety could be had by using the features discussed next to check that the trapped error was the one expected.

43.6.8.1. Obtaining Information about an Error

Exception handlers frequently need to identify the specific error that occurred. There are two ways to get information about the current exception in PL/pgSQL : special variables and the GET STACKED DIAGNOSTICS command.

Within an exception handler, the special variable SQLSTATE contains the error code that corresponds to the exception that was raised (refer to Table A.1 for a list of possible error codes). The special variable SQLERRM contains the error message associated with the exception. These variables are undefined outside exception handlers.

Within an exception handler, one may also retrieve information about the current exception by using the GET STACKED DIAGNOSTICS command, which has the form:

Each item is a key word identifying a status value to be assigned to the specified variable (which should be of the right data type to receive it). The currently available status items are shown in Table 43.2.

Table 43.2. Error Diagnostics Items

If the exception did not set a value for an item, an empty string will be returned.

Here is an example:

43.6.9. Obtaining Execution Location Information

The GET DIAGNOSTICS command, previously described in Section 43.5.5, retrieves information about current execution state (whereas the GET STACKED DIAGNOSTICS command discussed above reports information about the execution state as of a previous error). Its PG_CONTEXT status item is useful for identifying the current execution location. PG_CONTEXT returns a text string with line(s) of text describing the call stack. The first line refers to the current function and currently executing GET DIAGNOSTICS command. The second and any subsequent lines refer to calling functions further up the call stack. For example:

GET STACKED DIAGNOSTICS . PG_EXCEPTION_CONTEXT returns the same sort of stack trace, but describing the location at which an error was detected, rather than the current location.

Submit correction

If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.

Copyright © 1996-2023 The PostgreSQL Global Development Group

Источник

Syntax errors are quite common while coding.

But, things go for a toss when it results in website errors.

PostgreSQL error 42601 also occurs due to syntax errors in the database queries.

At Bobcares, we often get requests from PostgreSQL users to fix errors as part of our Server Management Services.

Today, let’s check PostgreSQL error in detail and see how our Support Engineers fix it for the customers.

What causes error 42601 in PostgreSQL?

PostgreSQL is an advanced database engine. It is popular for its extensive features and ability to handle complex database situations.

Applications like Instagram, Facebook, Apple, etc rely on the PostgreSQL database.

But what causes error 42601?

PostgreSQL error codes consist of five characters. The first two characters denote the class of errors. And the remaining three characters indicate a specific condition within that class.

Here, 42 in 42601 represent the class “Syntax Error or Access Rule Violation“.

In short, this error mainly occurs due to the syntax errors in the queries executed. A typical error shows up as:

Here, the syntax error has occurred in position 119 near the value “parents” in the query.

How we fix the error?

Now let’s see how our PostgreSQL engineers resolve this error efficiently.

Recently, one of our customers contacted us with this error. He tried to execute the following code,

CREATE OR REPLACE FUNCTION prc_tst_bulk(sql text)
RETURNS TABLE (name text, rowcount integer) AS
$$
BEGIN
WITH m_ty_person AS (return query execute sql)
select name, count(*) from m_ty_person where name like '%a%' group by name
union
select name, count(*) from m_ty_person where gender = 1 group by name;
END
$$ LANGUAGE plpgsql;

But, this ended up in PostgreSQL error 42601. And he got the following error message,

ERROR: syntax error at or near "return"
LINE 5: WITH m_ty_person AS (return query execute sql)

Our PostgreSQL Engineers checked the issue and found out the syntax error. The statement in Line 5 was a mix of plain and dynamic SQL. In general, the PostgreSQL query should be either fully dynamic or plain. Therefore, we changed the code as,

RETURN QUERY EXECUTE '
WITH m_ty_person AS (' || sql || $x$)
SELECT name, count(*)::int FROM m_ty_person WHERE name LIKE '%a%' GROUP BY name
UNION
SELECT name, count(*)::int FROM m_ty_person WHERE gender = 1 GROUP BY name$x$;

This resolved the error 42601, and the code worked fine.

[Need more assistance to solve PostgreSQL error 42601?- We’ll help you.]

Conclusion

In short, PostgreSQL error 42601 occurs due to the syntax errors in the code. Today, in this write-up, we have discussed how our Support Engineers fixed this error for our customers.

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