| PostgreSQL 8.0.1 Documentation | ||||
|---|---|---|---|---|
| Prev | Fast Backward | Chapter 9. Functions and Operators | Fast Forward | Next |
9.14. Array Functions and Operators
Table 9-35 shows the operators available for array types.
Table 9-35. array Operators
| Operator | Description | Example | Result |
|---|---|---|---|
| = | equal | ARRAY[1.1,2.1,3.1]::int[] = ARRAY[1,2,3] | t |
| <> | not equal | ARRAY[1,2,3] <> ARRAY[1,2,4] | t |
| < | less than | ARRAY[1,2,3] < ARRAY[1,2,4] | t |
| > | greater than | ARRAY[1,4,3] > ARRAY[1,2,4] | t |
| <= | less than or equal | ARRAY[1,2,3] <= ARRAY[1,2,3] | t |
| >= | greater than or equal | ARRAY[1,4,3] >= ARRAY[1,4,3] | t |
| || | array-to-array concatenation | ARRAY[1,2,3] || ARRAY[4,5,6] | {1,2,3,4,5,6} |
| || | array-to-array concatenation | ARRAY[1,2,3] || ARRAY[[4,5,6],[7,8,9]] | {{1,2,3},{4,5,6},{7,8,9}} |
| || | element-to-array concatenation | 3 || ARRAY[4,5,6] | {3,4,5,6} |
| || | array-to-element concatenation | ARRAY[4,5,6] || 7 | {4,5,6,7} |
See Section 8.10 for more details about array operator behavior.
Table 9-36 shows the functions available for use with array types. See Section 8.10 for more discussion and examples of the use of these functions.
Table 9-36. array Functions
| Function | Return Type | Description | Example | Result |
|---|---|---|---|---|
array_cat (anyarray, anyarray) | anyarray | concatenate two arrays | array_cat(ARRAY[1,2,3], ARRAY[4,5]) | {1,2,3,4,5} |
array_append (anyarray, anyelement) | anyarray | append an element to the end of an array | array_append(ARRAY[1,2], 3) | {1,2,3} |
array_prepend (anyelement, anyarray) | anyarray | append an element to the beginning of an array | array_prepend(1, ARRAY[2,3]) | {1,2,3} |
array_dims (anyarray) | text | returns a text representation of array's dimensions | array_dims(array[[1,2,3], [4,5,6]]) | [1:2][1:3] |
array_lower (anyarray, integer) | integer | returns lower bound of the requested array dimension | array_lower(array_prepend(0, ARRAY[1,2,3]), 1) | 0 |
array_upper (anyarray, integer) | integer | returns upper bound of the requested array dimension | array_upper(ARRAY[1,2,3,4], 1) | 4 |
array_to_string (anyarray, text) | text | concatenates array elements using provided delimiter | array_to_string(array[1, 2, 3], '~^~') | 1~^~2~^~3 |
string_to_array (text, text) | text[] | splits string into array elements using provided delimiter | string_to_array( 'xx~^~yy~^~zz', '~^~') | {xx,yy,zz} |
