diff options
author | Bruce Momjian | 2002-12-27 14:10:29 +0000 |
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committer | Bruce Momjian | 2002-12-27 14:10:29 +0000 |
commit | 1868b0be44e44f7c03516559625a966176af5f83 (patch) | |
tree | 5dc495f71a3e79ad820001de190b89d23906bf9d | |
parent | 9a39ba4b0fe6dc6b3744b31bc5115837b88677ae (diff) |
Small fix in documentation and some examples of usage. Please, apply to
7.3 and current CVS
Oleg Bartunov
-rw-r--r-- | contrib/intarray/README.intarray | 41 |
1 files changed, 39 insertions, 2 deletions
diff --git a/contrib/intarray/README.intarray b/contrib/intarray/README.intarray index 6c8bc13e17..a1ffef1e4a 100644 --- a/contrib/intarray/README.intarray +++ b/contrib/intarray/README.intarray @@ -8,22 +8,59 @@ signature with length of 4096 bits to represent sets). All work was done by Teodor Sigaev ([email protected]) and Oleg Bartunov ([email protected]). See http://www.sai.msu.su/~megera/postgres/gist -for additional information. Andrey Oktyabrski has done a great work on +for additional information. Andrey Oktyabrski did a great work on adding new functions and operations. FUNCTIONS: int icount(int[]) - the number of elements in intarray + +test=# select icount('{1,2,3}'::int[]); + icount +-------- + 3 +(1 row) + int[] sort(int[], 'asc' | 'desc') - sort intarray + +test=# select sort('{1,2,3}'::int[],'desc'); + sort +--------- + {3,2,1} +(1 row) + int[] sort(int[]) - sort in ascending order int[] sort_asc(int[]),sort_desc(int[]) - shortcuts for sort + int[] uniq(int[]) - returns unique elements + +test=# select uniq(sort('{1,2,3,2,1}'::int[])); + uniq +--------- + {1,2,3} +(1 row) + int idx(int[], int item) - returns index of first intarray matching element to item, or '0' if matching failed. + +test=# select idx('{1,2,3,2,1}'::int[],2); + idx +----- + 2 +(1 row) + + int[] subarray(int[],int START [, int LEN]) - returns part of intarray starting from element number START (from 1) and length LEN. +test=# select subarray('{1,2,3,2,1}'::int[],2,3); + subarray +---------- + {2,3,2} +(1 row) + + OPERATIONS: int[] && int[] - overlap - returns TRUE if arrays has at least one common elements. @@ -33,7 +70,7 @@ OPERATIONS: int[] + int - push element to array ( add to end of array) int[] + int[] - merge of arrays (right array added to the end of left one) int[] - int - remove entries matched by right argument from array - int[] - int[] - remove left array from right + int[] - int[] - remove right array from left int[] | int - returns intarray - union of arguments int[] | int[] - returns intarray as a union of two arrays int[] & int[] - returns intersection of arrays |