PostgreSQL CASEs can have multiple conditions. There are a handful of entries in the table where the name of country and capital is the same. You can add this to your previously constructed CASE - SELECT name, continent, indep_year, CASE WHEN (indep_year < 1900) AND (countries.name = co...
*/ StaticAssertDecl(THRESHOLD_SUBTRANS_CLOG_OPT <= PGPROC_MAX_CACHED_SUBXIDS, "group clog threshold less than PGPROC cached subxids"); /* * When there is contention on XactSLRULock, we try to group multiple * updates; a single leader process will perform transaction status * updates ...
WHEN value2 THEN result2 ... ELSE default_result END; Searched CASE Unlike the Simple CASE that evaluates a single expression against multiple values, the Searched CASE evaluates multiple conditions. Its structure is: CASE WHEN condition1 THEN result1 WHEN condition2 THEN result2 ... ELSE defau...
If any of the upper 25/17 bits are not zero, the code point is broken into multiple 1-byte (UTF-8) or 2-byte (UTF-16) sequences based on someclever rules, One of the very nice features of Unicode is that any code point where the upper 25 bits are zero is exactly the same as...
CASE condition WHEN condition value THEN statement ELSE additional statement; Example We can use CASE to evaluate multiple conditions for a single variable, “job_id.” If “job_id” is “ACCOUNT,” the salary increase is 10%; if “job_id” is “IT_PROG,” the salar...
*/ oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory); /* * Evaluate the qual conditions one at a time. If we find a FALSE result, * we can stop evaluating and return FALSE --- the AND result must be * FALSE. Also, if we find a NULL result when resultForNull ...
Fixed the error - “column ... does not exist” when using table.column with alias defined for table or schema_name.table.column in set clause of update queries. Fixed issue of incorrect schema resolution for multiple functions in query statement. Fixed an issue for a few variants of DELETE...
once, rather than assume they can read it multiple times and get the same answer each time. (Use volatile-qualified pointers when doing this, to ensure that the C compiler does exactly what you tell it to.) Another important activity that uses the shared ProcArray is GetOldestXmin, ...
Ans:PostgreSQL has several features that make it well-suited for handling large data and high traffic. It supports horizontal scaling through the use of read replicas and connection pooling which allows multiple connections to be handled by a single backend process. Additionally, it also has advance...
exists already.*/voidsmgrreleaserellocator(RelFileLocatorBackendrlocator){SMgrRelationreln;/* Nothing to do if hashtable not set up */if(SMgrRelationHash==NULL)return;reln=(SMgrRelation)hash_search(SMgrRelationHash,&rlocator,HASH_FIND,NULL);if(reln!=NULL)smgrrelease(reln);}/** smgrreleaseall(...