This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision Next revision | Previous revision | ||
|
dev:sql:functions:contains:home [2011/01/23 23:16] els |
dev:sql:functions:contains:home [2016/06/28 22:38] (current) |
||
|---|---|---|---|
| Line 5: | Line 5: | ||
| ===== SQL Functions: $CONTAINS ====== | ===== SQL Functions: $CONTAINS ====== | ||
| - | **[[dev:sql:functions:contains:home|Overview]]** | | + | **[[dev:sql:functions:contains:home|Description]]** | |
| [[dev:sql:functions:contains:syntax|Syntax]] | | [[dev:sql:functions:contains:syntax|Syntax]] | | ||
| - | [[dev:sql:functions:contains:Customization]] | | + | [[dev:sql:functions:contains:customization|Customization]] | |
| [[dev:sql:functions:contains:examples|Examples]] | [[dev:sql:functions:contains:examples|Examples]] | ||
| Line 20: | Line 20: | ||
| There is no standardized SQL to support textual searches involving keyword searches, proximity searches, synonym searches, spellchecking and similar features. Some database vendors have implemented their own independent approaches, but they vary between databases. | There is no standardized SQL to support textual searches involving keyword searches, proximity searches, synonym searches, spellchecking and similar features. Some database vendors have implemented their own independent approaches, but they vary between databases. | ||
| - | + | This function returns a BOOLEAN datatype and can only be referenced in the WHERE clause of a SELECT statement. | |
| - | The CHARACTER_LENGTH function returns the number of characters in a string. The abbreviation, CHAR_LENGTH, is supported as a synonym for CHARACTER_LENGTH. | + | |
| - | + | ||
| - | CHARACTER_LENGTH should not be confused with $DATA_LENGTH and $COLUMN_LENGTH. $DATA_LENGTH returns the number of characters plus the null-terminator for C STRING datatypes. $COLUMN_LENGTH returns the length of the column as declared in the table. | + | |
| - | + | ||
| - | This function returns an INTEGER datatype. | + | |
| - | + | ||
| - | ===== Syntax ==== | + | |
| - | CHAR[ACTER]_LENGTH ( character_expression ) | + | |
| - | + | ||
| - | == character_expression == | + | |
| - | Required. Any expression that returns a character-class datatype. Examples of expressions are columns, concatenations of columns, literal strings and functions that return a character datatype. | + | |
| - | + | ||
| - | ==== Examples ==== | + | |
| - | === Example 1: Column === | + | |
| - | <code> | + | |
| - | > select name, character_length(name) len from individuals; | + | |
| - | + | ||
| - | NAME LEN | + | |
| - | -------------------------------------------------- ----------- | + | |
| - | MS. MARY LEWIS 14 | + | |
| - | MRS. ALICE R TOLLIVER 21 | + | |
| - | MR. SIDNEY K TOLLIVER 21 | + | |
| - | MRS. JENNIFER J HOPKINS 23 | + | |
| - | MR. CHARLIE HOPKINS 19 | + | |
| - | MS. KIMBERLY BLUE 17 | + | |
| - | KATHLEEN TUCKER 15 | + | |
| - | + | ||
| - | </code> | + | |
| - | + | ||
| - | === Example 2: Character Expression === | + | |
| - | <code> | + | |
| - | > select gender, name, char_length(gender || name) len from individuals; | + | |
| - | + | ||
| - | G NAME LEN | + | |
| - | - -------------------------------------------------- ----------- | + | |
| - | F MS. MARY LEWIS 15 | + | |
| - | F MRS. ALICE R TOLLIVER 22 | + | |
| - | M MR. SIDNEY K TOLLIVER 22 | + | |
| - | F MRS. JENNIFER J HOPKINS 24 | + | |
| - | M MR. CHARLIE HOPKINS 20 | + | |
| - | F MS. KIMBERLY BLUE 18 | + | |
| - | F KATHLEEN TUCKER 16 | + | |
| - | + | ||
| - | </code> | + | |
| ==== ==== | ==== ==== | ||